024339   Plessis H D;Masilela T (Research Use and Impact Assessment (RIA) Unit, Human Sciences Research Council (HSRC), South Africa, Email: hesterdup@gmail.com) : Report on the human sciences research council (HSRC) 2012 conference- the re-emergence of astronomy in Africa-a transdisciplinary interface of knowledge systems. J scient Temp 2013, 1(3-4), 219-26.

8 ref

024338   Jiang Y;Baoyin H (State Key Laboratory of Astronautic Dynamics, Xi'an Satellite Control Center, Xi'an-710 043, China, Email: jiangyu_xian_china@163.com) : Orbital mechanics near a rotating asteroid. J Astrophys Astr 2014, 35(1), 17-38.

This study investigates the different novel forms of the dynamical equations of a particle orbiting a rotating asteroid and the effective potential, the Jacobi integral, etc. on different manifolds. Nine new forms of the dynamical equations of a particle orbiting a rotating asteroid are presented, and the classical form of the dynamical equations has also been found. The dynamical equations with the potential and the effective potential in scalar form in the arbitrary body-fixed frame and the special body-fixed frame are presented and discussed. Moreover, the simplified forms of the effective potential and the Jacobi integral have been derived. The dynamical equation in coefficient-matrix form has been derived. Other forms of the dynamical equations near the asteroid are presented and discussed, including the Lagrange form, the Hamilton form, the symplectic form, the Poisson form, the Poisson-bracket form, the cohomology form, and the dynamical equations on Kahler manifold and another complex manifold. Novel forms of the effective potential and the Jacobi integral are also presented. The dynamical equations in scalar form and coefficient-matrix form can aid in the study of the dynamical system, the bifurcation, and the chaotic motion of the orbital dynamics of a particle near a rotating asteroid. The dynamical equations of a particle near a rotating asteroid are presented on several manifolds, including the symplectic manifold, the Poisson manifold, and complex manifolds, which may lead to novel methods of studying the motion of a particle in the potential field of a rotating asteroid.

2 illus, 1 table, 37 ref

024337   Hong-tao W (NO, Faculty of Physics and Electronic Information, LangFang Teacher's Coll, LangFang, China, Email: hthtwang@126.com) : Analysis of optical variations of BL lac object AO 0235+164. J Astrophys Astr 2014, 35(1), 87-95.

Historical optical BVRI band data are combined on the BL Lac object AO 0235 + 164. In order to examine the possible existence of lags and correlations between variations in different optical bands from this source, a statistical analysis is performed through the Discrete Correlation Function (DCF) method. Monte Carlo simulations called Flux Redistribution/Random Subset Selection (FR/RSS) are performed to obtain statistically meaningful values for the cross-correlation time lags and their related uncertainties. The analysis confirms that the variations in different optical light curves are strongly correlated, with no or very weak lag within the errors. Long term variability of color indices are also analysed. No color variabilities are found.

4 illus, 3 tables, 29 ref

024336   Dwivedee D;Nayak B;Jamil M;Singh L P; Myrzakulov R (Physics Dep, Utkal Univ, Vanivihar, Bhubaneswar-751 004, Email: bibeka@iopb.res.in) : Evolution of primordial black holes in loop quantum cosmology. J Astrophys Astr 2014, 35(1), 97-106.

In this work, author study the evolution of primordial black holes within the context of loop quantum cosmology. First we calculate the scale factor and energy density of the Universe for different cosmic era and then taking these as inputs, we study evolution of primordial black holes. From our estimation it is found that accretion of radiation does not affect evolution of primordial black holes in loop quantum cosmology. We also conclude that due to slow variation of scale factor, the upper bound on initial mass fraction of presently evaporating PBHs are much greater in loop quantum cosmology than the standard case.

1 illus, 2 tables, 62 ref

024335   Calabro E (Physics Dep, Messina Univ, Viale D'Alcontres, 31-98166, Messina, Italy, Email: e.calabro@yahoo.com) : Interacting winds in eclipsing symbiotic systems- the case study of EG andromedae. J Astrophys Astr 2014, 35(1), 69-85.

Reports the mathematical representation of the so called eccentric eclipse model, whose numerical solutions can be used to obtain the physical parameters of a quiescent eclipsing symbiotic system. Indeed the nebular region produced by the collision of the stellar winds should be shifted to the orbital axis because of the orbital motion of the system. This mechanism is not negligible, and it led us to modify the classical concept of an eclipse. The orbital elements obtained from spectroscopy and photometry of the symbiotic EG Andromedae were used to test the eccentric eclipse model. Consistent values for the unknown orbital elements of this symbiotic were obtained. The physical parameters are in agreement with those obtained by means of other simulations for this system.

5 illus, 3 tables, 50 ref

024334   Bruevich E A;Bruevich V V;Yakunina G V (NO, Sternberg Astronomical Institute, Moscow State Univ, Universitetsky pr. 13, Moscow-119 992, Russia, Email: red-field@yandex.ru) : Changed relation between solar 10.7-cm radio flux and some activity indices which describe the radiation at different altitudes of atmosphere during cycles 21-23. J Astrophys Astr 2014, 35(1), 1-15.

The correlation coefficients of the linear regression of six solar indices versus 10.7 cm radio flux F10.7 were analysed in solar cycles 21, 22 and 23. We also analysed the interconnection between these indices and F_10.7 with help of approximation by polynomials of second order. The indices we have studied in this paper are: the relative sunspot numbers - SSN, 530.3 nm coronal line flux - F₅₃₀ the total solar irradiance -TSI, Mg II 280 nm core-to-wing ratio UV-index, the - 24 - Flare Index - FI and the counts of flares. In most cases the regressions of these solar indices vs. F10.7 are close to the linear regression except the moments of time near the minimums and maximums of the 11-year activity. For the linear regressions, we found that correlation coefficients K_corr (t) for the solar indices vs. F_10.7 and SSN dropped to their minimum values twice during each 11-year cycle.

4 illus, 2 tables, 37 ref

024333   Bhatt H;Pandey J C;Singh K P;Sagar R;Brijesh Kumar (Astrophysical Sciences Div, Bhabha Atomic Research Center, Trombay, Mumbai-400 085, Email: mshimali@gmail.com) : X-ray flares observed from six stars located in the region of star clusters NGC 869 and IC 2602. J Astrophys Astr 2014, 35(1), 39-54.

Presents for the first time, an analysis of seven intense X-ray flares observed from six stars (LAV 796, LAV 1174, SHM2002 3734, 2MASS 02191082+5707324, V553 Car, V557 Car). These stars are located in the region of young open star clusters NGC 869 and IC 2602. These flares detected in the XMM-Newton data show a rapid rise (10-40 min) and a slow decay (20-90 min). The X-ray luminosities during the flares in the energy band 0.3-7.5 keV are in the range of 10^{29.9 to 1031.7 erg s-1. The strongest flare was observed with the ratio <126>13 for count rates at peak of the flare to the quiescent intensity. The maximum temperature during the flares has been found to be <126> 100 MK. The semi-loop lengths for the flaring loops are estimated to be of the order of 1010 cm. The physical parameters of the flaring structure, the peak den-sity, pressure and minimum magnetic field required to confine the plasma have been derived and found to be consistent with flares from pre-main sequence stars in the Orion and the Taurus-Auriga-Perseus region.}

2 illus, 4 tables, 66 ref

023284   Arya A S;Kiran Kumar A S (NO, Space Applications Centre (ISRO), Ahmedabad-380 015, Email: arya_as@sac.isro.gov.in) : Mars orbiter mission prepared to photograph mars: some results from earth imaging experiment. Curr Sci 2014, 106(5), 661.

1 illus

021252   Venkat Raman M;Basha G;Eswariah S;Roja Raman M (NO, National Atmospheric Research Laboratory (NARL), Gadanki-517 112, Email: vratnam@narl.gov.in) : Lower and middle atmospheric responses to the 22 July 2009 total solar eclipse. Indian J Radio Space Phys 2014, 43(1), 91-102.

In the present study, the effect of total solar eclipse, occurred on 22 July 2009, on water vapour in the troposphere, refractivity and temperature in the troposphere and the stratosphere using the observations available from COSMIC GPS RO, is reported. The investigation is extended to the entire middle atmosphere using SABER aboard TIMED satellite to study the response in the temperature and ozone. A significant enhancement in the water vapour and the refractivity in the lower and middle troposphere are noticed on the eclipse day when compared to non-eclipse days. Using the GPS RO observations, it is also found that the temperature responds differently at different altitudes, i.e. cooling in the troposphere and warming in the stratosphere. Similar features in temperature are also noticed in SABER observations below 40 km. Above 40 km altitude, cooling is observed up to an altitude of 70 km, therein again warming is noticed. An increase in ozone concentration is found throughout the middle atmosphere except near 30 km. Tropopause altitude is also observed to vary significantly during the solar eclipse with decrease (increase) in the altitude (temperature) of about 1-1.5 km (3-5 K). Large perturbations in the temperature, due to gravity waves in the stratosphere and the mesosphere, are noticed on the eclipse day and found westward propagating as expected. For the first time, evidences of solar eclipse in the entire lower and middle atmosphere is presented using ground based and satellite borne observations.

8 illus, 25 ref

021251   Tickoo A K et al (Astrophysical Sciences Div, Bhabha Atomic Research Centre, , Mumbai 400 085, Email: aktickoo@barc.gov.in) : Long term performance evaluation of the TACTIC imaging telescope using ~400 h Crab Nebula observation during 2003-2010. Pramana J Phys 2014, 82(3), 585-605.

The TeV atmospheric Cherenkov telescope with imaging camera (TACTIC) γ-ray telescope has been in operation at Mt. Abu, India since 2001 to study TeV γ-ray emission from celestial sources. During the last 10 years, apart from consistently detecting a steady signal from the Crab Nebula above ~1.2 TeV energy, at a sensitivity level of ~5.0σ in ~25 h, the telescope has also detected flaring activity from Mrk 421 and Mrk 501 on several occasions. Although we used Crab Nebula data partially, in some of the reported results, primarily for testing the validity of the full data analysis chain, the main aim of this work is to study the long term performance of the TACTIC telescope by using consolidated data collected between 2003 and 2010. The total on-source data, comprising ~402 h, yields an excess of ~(3742±192) γ-ray events with a statistical significance of ~19.9σ . The off-source data, comprising ~107 h of observation, is found to be consistent with a no-emission hypothesis, as expected. The resulting γ-ray rate for the onsource data is determined to be ~(9.31±0.48) h^-1. A power law fit (dΦ/dE = ƒ₀E^-Γ) with ƒ₀ ~ (2.66±0.29) x 10-11 cm^-2 s^-1 TeV^-1 and Γ ~ 2.56±0.10 is found to provide reasonable fit to the inferred differential spectrum within statistical uncertainties. The spectrum matches reasonably well with that obtained by other groups. A brief summary of the improvements in the various subsystems of the telescope carried out recently, which has resulted in a substantial improvement in its detection sensitivity (viz., ~5σ in an observation period of ~13 h as compared to ~25 h earlier) are also presented in this paper. Encouraged by the detection of strong γ-ray signals from Mrk 501 and Mrk 421 on several occasions, there is considerable scope for the TACTIC telescope to monitor similar TeV γ-ray emission activity from other active galactic nuclei on a long-term basis.

7 illus, 3 tables, 41 ref

021250   Ramkumar T K;Ghosh P;Krishna Reddy K;Niranjan Kumar K;Balaji Kumar S;Hari Krishna Reddy A;Venkatrami Reddy M; Surendra Prasad S B (NO, National Atmospheric Research Laboratory, PB NO 123, Tirupati-517 502, Email: tkram@narl.gov.in) : Large Scale anomalous temperature and wind variations in the lower and middle atmospheres during the solar eclipse of 15 January 2010. Indian J Radio Space Phys 2014, 43(1), 75-82.

During 12-17 January 2010 centered around 15 January, annular solar eclipse event occurred over the Indian tropical region. The Indian Space Research Organisation (ISRO) sponsored and provided 18 GPS radiosondes (ISRO developed Dr Pisharoty sondes) to the Department of Physics, Yogi Vemana University, Kadapa (14.5°N, 78.9°E), to study the effects of solar eclipse on the atmospheric dynamics and structure. The analyses of the data obtained from these radiosondes launched by balloons indicate that during this eclipse period, the atmosphere experienced ever recorded largest stratospheric cooling (maximum cooling of <126>15 K at 36 km). As a first time ever report, significant localized variations in the strength of the large-scale zonal Walker and meridional Hadley circulations were also found over the Indian longitude region during this solar eclipse event.

7 illus, 21 ref

021249   Ramesh K;Sridharan S;Vijaya Bhaskara Rao S; Raghunath K;Bhavani Kumar Y (Physics Dep, Sri Venkateswara Univ, Tirupati-517 502, Email: susridharan@narl.gov.in) : Rayleigh lidar observations of mesospheric inversion layers over Gadanki (13.5 N, 79.2 E) and their relationship with gravity wave activity. Indian J Radio Space Phys 2014, 43(1), 83-90.

Fifteen nights of Rayleigh lidar temperature profiles over Gadanki (13.5°N, 79.2°E) for the period January - February 1999 show the presence of mesospheric inversion layers (MILs) on ten nights indicating their frequent occurrences over low latitudes. The role of gravity waves in causing the MILs has been investigated using the temperature profiles derived from the half an hour integrated photon counts. The temperature deviations from the nightly mean temperature are inferred as due to gravity waves and potential energy per unit mass due to these waves; and their spectra are examined separating MIL nights and non-MIL nights. The spectra of potential energy per unit mass (E_p) computed from the temperature fluctuations attain broad band convective instability limit at mesospheric heights on MIL nights, whereas the spectra just tend to attain the limit on non-MIL nights at longer wavelengths. These results indicate that enhanced gravity wave growth and breaking due to convective instability may be the potential mechanism for the occurrence of these MILs.

8 illus, 8 ref

021248   Pandiyan J;Naresh B;Nagarajan R (P.G. Research Zoology & Wildlife Biology Dep, AVC College (Autonomous), Mannampandal, Mayiladuthurai, Tamilnadu, Email: dunlinpandiyan@gmil.com) : Spatial variations of shorebird community in the saltpans of East coast of Tamil Nadu, Southern India. Scient Trans Envir Technovation 2013, 7(1), 51-8.

Studied the spatial variations of bird species and invertebrates in the different saltpans of Kodikkarai regions of east coast of southern India. We selected five different saltpans and fortnightly quantification was made on birds and invertebrates. The birds were estimated by total count and the invertebrates were sampled at 20cm depth which used for foraging by shorebirds. In total 10345 of individual birds consisting of 46 species were using the saltpans as foraging grounds. In which, species of shorebirds used the saltpans more than the other bird species. Among the five saltpans, the Nedunthittu saltpan had highest density (21.08/ha.), diversity (H'=2.1092) and bird species richness (38) than the other saltpans. The bird density showed significant difference among the saltpans (P<60>0.05). Also, there was a positive relationship between the density of bird species and density of benthic organisms (P<60>0.05). From this study, it is inferred that the conservation, restoration and development of saltpans at coastal wetlands, is a viable approach to the conservation of birds especially migratory shorebirds.

4 illus, 1 table, 35 ref

021247   Dhaka S K;Malik V;Shibagaki Y;Hashiguchi H; Fukao S;Shimomai T;Chun H Y;Takahashi M (Physics Dep, Rajdhani College, Delhi Univ, Raja Garden, New Delhi-110 015, Email: skdhaka@yahoo.com) : Comparison of vertical wavelengths of gravity waves emitted by convection in the UTLS region at Koto Tabang (0.20 S, 100.32 E) and Gadanki (13.5 N, 79.2 E) using radars. Indian J Radio Space Phys 2014, 43(1), 24-40.

Observations of wind components and convection systems were made using suite of instruments centered on the Equatorial Atmosphere Radar (EAR) at Koto Tabang, Indonesia (0.20°S, 100.32°E) during April-May 2004 in the first Coupling Processes in Equatorial Atmosphere (CPEA) campaign. Experiments were also conducted using Indian Mesosphere Stratosphere Troposphere (MST) Radar in India at Gadanki (13.5°N, 79.2°E) during June 2000, which is highly convective season after the onset of south - west monsoon over southern part of India. During convective events, radar reflectivity showed the temporal evolution of convection with different vertical velocities and depth of penetration (seen from mid troposphere to upper troposphere). Observations covered several convective events that enabled to present forcing scale in the vertical direction by observing vertical wavelength (λ_z) associated with gravity wave structure and updrafts. Analysis of five convection events over Indonesian region and two convection events over Indian region revealed that λ_z of gravity waves mostly dominated in the range of 1-3 km between 10 and 20 km heights immediately after passing the convective storm over the radar sites. On the other hand, vertical wavelengths computed during formation of convective updrafts over a period of <126>1 hour (typical time of storm) were about 5-8 km, which is a representative of updrafts characteristics. At both locations, λ_z increases gradually after the convection moved away from radars. Dynamics in the upper troposphere and lower stratosphere seems affected by the interaction of short λ_z (<126>1-3 km) gravity waves with then prevailing easterly wind. Dominant wave periods were observed in the range of 10-60 min with preference of shorter wave periods (<126>10-20 min) at Gadanki and longer periods (<126>30-50 min) at Koto Tabang possibly having a relationship with quasi-periodic behaviour of rainfall and updrafts formation patterns.

12 illus, 38 ref

021246   Das S S;Kumar K K;Uma K N;Ratnam M V;Patra A K;Das S K;Ghosh A K;Jain A R (Space Physical Laboratory, Vikram Sarabhai Space Centre, ISRO PO, Trivandrum-695 022, Email: dassiddhu@yahoo.com) : Modulation of thermal structure in the upper troposphere and lower stratosphere (UTLS) region by inertia gravity waves: a case study inferred from simultaneous MST radar and GPS sonde observations. Indian J Radio Space Phys 2014, 43(1), 11-23.

The observations of multiple layer structures in the MST radar backscattering echoes in the upper troposphere and lower stratosphere (UTLS) region are discussed in this paper. The fact remains same that the enhanced echoes seen in the radar backscattering are due to the strong positive and negative thermal gradients. Simultaneous observations of MST radar (1 hourly) and GPS sonde (6 hourly) over a tropical station Gadanki (13.5°N, 79.2°E) reveal the presence of 1.5-2 km vertical wavelength in the winds, temperature and radar backscattering echoes in the UTLS region during Indian summer monsoon (ISM). The analysis also reveals that the presence of inertia gravity wave (IGW) triggered due to tropical easterly jet (TEJ) associated with ISM is the prime candidate for the observed thermal gradients in the UTLS region.

12 illus, 43 ref

018051   Subramanian S;Subramaniam A;Simard L;Gillies K;Ramaprakash A N;Anupama G C;Stalin C S;Ravindranath S;Reddy B E (NO, Indian Institute of Astrophysics, Koramangala, Bangalore-560 034, Email: smitha@iiap.res.in) : Generation of a near infra-red guide star catalog for thirty-meter telescope observations. J Astrophys Astr 2013, 34(2), 175-92.

Requirements for the production of a near Infra-Red Guide Star Catalog (IRGSC) for Thirty Meter Telescope (TMT) observations are identified and presented. A methodology to compute the expected J band magnitude of stellar sources from their optical (g, r, i) magnitudes is developed. The computed and observed J magnitudes of sources in three test fields are compared and the methodology developed is found to be satisfactory for the magnitude range, J_Vega = 16-22 mag. From this analysis, we found that for the production of final TMT IRGSC (with a limiting magnitude of J_Vega = 22 mag), we need g, r, i bands optical data which go up to i_AB <126> 23 mag. Fine tuning of the methodology developed, such as using Spectral Energy Distribution (SED) template fitting for optimal classification of stars in the fainter end, incorporating spectral libraries in the model, to reduce the scatter, and modification of the existing colour-temperature relation to increase the source density are planned for the subsequent phase of this work.

6 illus, 4 ref

018050   Simard L (NO, TMT Observatory Corporation, 1111 South Arroyo Parkway, Suite 200, Pasadena, CA 91105, USA, Email: luc.simard@tmt.org) : Thirty-meter telescope: science and instrumentation for a next-generation observatory. J Astrophys Astr 2013, 34(2), 97-120.

The Thirty-Meter Telescope international observatory will enable transformational observations over the full cosmic timeline all the way from the first luminous objects in the Universe to the planets and moons of the own solar system. To realize its full scientific potential, TMT will be equipped with a powerful suite of adaptive optics systems and science instruments. Three science instruments will be available at first light: an optical multi-object spectrometer, a near-infrared multi-slit spectrometer and a diffraction-limited near-infrared imager and integral field spectrometer. In addition to these three instruments, a diverse set of new instruments under study will bring additional workhorse capabilities to serve the science interests of a broad user community. The development of TMT instruments represents a large, long-term program that offers a wide range of opportunities to all TMT partners.

6 illus, 2 tables, 27 ref

018049   Sengupta S (NO, Indian Institute of Astrophysics, Koramangala, 2nd Block, Bangalore-560 034, Email: sujan@iiap.res.in) : Spectro-polarimetry of self-luminous extrasolar planets. J Astrophys Astr 2013, 34(2), 151-5.

Planets which are old and close to their parent stars are considered as reflecting planets because their intrinsic temperature is extremely low but they are heated strongly by the impinging stellar radiation and hence radiation of such planets are the reflected star light that is governed by the stellar radiation, orbital distance and albedo of the planet. These planets cannot be resolved from the host stars. The second kind of exoplanets are those which are very young and hence they have high intrinsic temperature. They are far away from their star and so they can be resolved by blocking the star-light. It is now realized that radiation of such planets are linearly polarized due to atmospheric scattering and polarization can determine various physical properties including the mass of such directly detected self-luminous exoplanets. It is suggested that a spectropolarimeter of even low spectral resolution and with a capacity to record linear polarization of 0.5-1 % at the thirty-meter telescope would immensely help in understanding the atmosphere, especially the cloud chemistry of the self-luminous and resolvable exoplanets.

2 illus, 15 ref

018048   Sanders G H (Physics, Mathematics and Astronomy Div, California Institute of Technology, Pasadena, CA 91125, USA, Email: sanders@tmt.org) : Thirty meter telescope (TMT): an international observatory. J Astrophys Astr 2013, 34(2), 81-6.

The Thirty Meter Telescope (TMT) will be the first truly global ground-based optical/infrared observatory. It will initiate the era of extremely large (30-meter class) telescopes with diffraction limited performance from its vantage point in the northern hemisphere on Mauna Kea, Hawaii, USA. The astronomy communities of India, Canada, China, Japan and the USA are shaping its science goals, suite of instrumentation and the system design of the TMT observatory. With large and open Nasmyth-focus platforms for generations of science instruments, TMT will have the versatility and flexibility for its envisioned 50 years of forefront astronomy. The TMT design employs the filled-aperture finely-segmented primary mirror technology pioneered with the W.M. Keck 10-meter telescopes. With TMT's 492 segments optically phased, and by employing laser guide star assisted multi-conjugate adaptive optics, TMT will achieve the full diffraction limited performance of its 30-meter aperture, enabling unprecedented wide field imaging and multi-object spectroscopy. The TMT project is a global effort of its partners with all partners contributing to the design, technology development, construction and scientific use of the observatory. TMT will extend astronomy with extremely large telescopes to all of its global communities.

1 illus, 12 ref

018047   Reddy B E (NO, Indian Institute of Astrophysics, Koramangala, Bangalore-560 034, Email: ereddy@iiap.res.in) : India's paricipation in the thirty-meter telescope project. J Astrophys Astr 2013, 34(2), 87-95.

In 2010, the Department of Science and Technology (DST), Govt. of India, approved astronomers' proposal of India joining the international consortium of the USA, Japan, Canada and China to build and operate the next generation mega ground based optical and infrared telescope known as the Thirty-Meter Telescope (TMT) after its aperture size of 30-meter diameter. Since then, India is engaged in many aspects of the TMT project, both at technical and policy levels. In this article, I confine to the description of India's efforts leading up to the decision to join the consortium, and the progress made since then with respect to India's technical contributions to the project.

4 illus, 2 tables, 8 ref

018046   Pandey S B (NO, Aryabhatta Research Institute of Observational Sciences, Manora Peak, Nainital-263 129, Email: shashi@aries.res.in) : Core-collapse supernovae and gamma-ray bursts in TMT era. J Astrophys Astr 2013, 34(2), 157-73.

Study of energetic cosmic explosions as a part of time domain astronomy is one of the key areas that could be pursued with upcoming Giant segmented optical-IR telescopes with a very large photon collecting area applying cutting edge technology. Existing 8-10 m class telescopes have been helpful to improve the knowledge about core-collapse super-novae, gamma-ray bursts and nature of their progenitors and explosion mechanisms. However, many aspects about these energetic cosmic explosions are still not well-understood and require much bigger telescopes and back-end instruments with high precision to address the evolution of massive stars and high-redshift Universe in more detail. In this presentation, possible thrust research areas towards core-collapse supernovae and gamma-ray bursts with the Thirty-Meter Telescope and back-end instruments are presented.

3 illus, 137 ref

018045   Ishwara Chandra C H (NO, National Centre for Radio Astrophysics, Tata Institute of Fundamental, Pune-411 007, Email: ishwar@ncra.tifr.res.in) : Synergy between radio and optical telescopes: optical followup of extragalactic radio sources. J Astrophys Astr 2013, 34(2), 141-9.

Distance measurement is a must to characterize any source in the sky. In the radio band, it is rarely possible to get distance or redshift measurements. The optical band is the most used band to get distance estimate of sources, even for those originally discovered in other bands of the electromagnetic spectrum. However, the spectroscopic redshift measurements even for fairly bright radio sample is grossly incomplete, implying un-explored discovery space. Here author discusses the scope of optical follow up of radio sources, in particular the radio loud AGNs, from the present generation radio telescopes.

2 illus, 37 ref

018044   Ellerbroek B L (NO, TMT Observatory Corporation, 1111 S. Arroyo Pkwy, Ste. 200, Pasadena, CA 91107, USA, Email: brente@caltech.edu) : Status report on the thirty meter telescope adaptive optics program. J Astrophys Astr 2013, 34(2), 121-39.

Provided an update on the recent development of the adaptive optics (AO) systems for the Thirty Meter Telescope (TMT) since mid-2011. The first light AO facility for TMT consists of the Narrow Field Infra-Red AO System (NFIRAOS) and the associated Laser Guide Star Facility (LGSF). This order 60 x 60 laser guide star (LGS) multi-conjugate AO (MCAO) architecture will provide uniform, diffraction-limited performance in the J, H and K bands over 17-30 arcsec diameter fields with 50 per cent sky coverage at the galactic pole, as is required to support TMT science cases. The NFIRAOS and LGSF subsystems completed successful preliminary and conceptual design reviews, respectively, in the latter part of 2011. We also report on progress in AO component prototyping, control algorithm development, and system performance analysis, and conclude with an outline of some possible future AO systems for TMT.

12 illus, 3 table, 25 ref

017013   Uma K N;Karanam K K;Das S S (Space Physics Laboratory, Vikram Sarabhai Space Centre, ISRO-PO, Thiruvananthapuram-695 022, Email: urmi_nmrf@yahoo.co.in) : Migrating and non-migrating diurnal and semi-diurnal tides over a tropical and an equatorial station. Indian J Radio Space Phys 2013, 42(5), 340-55.

VHF radar measurements of hourly winds in the lower atmosphere are utilized to study the diurnal and semi-diurnal tides over two key geographical locations, Gadanki (13.45°E, 79.18°E), India and Kotatabang (0.2°S, 100.2°E), Indonesia. The analysis shows that tidal amplitudes exhibit maxima in upper troposphere lower stratosphere (UTLS) region during June-September over Gadanki and during March and September over Kotatabang. The vertical wavelength is 3-5 km at Gadanki and 25-30 km at Kotatabang in UTLS region, which reveal the existence of non-migrating and migrating tides, respectively. The analysis shows the maximum rainfall during June-September over Gadanki, whereas uniform rainfall throughout the year over Kotatabang. The brightness temperature shows deep (at Gadanki) and shallow (at Kotatabang) convective clouds during these periods. The release of latent heat due to deep convective cloud is found to be the main source mechanism for non-migrating tides at Gadanki. The significance of The study lies in bringing out the important differences in tidal characteristics over equatorial and low latitude stations.

12 illus, 41 ref

017012   Sridharan S;Suresh M;Ramesh K (NO, National Atmospheric Research Laboratory, Gadanki, Pakala, Andhra Pradesh-517 112, Email: susridharan@narl.gov.in) : VHF radar observations of mesospheric echoes and their relationship with thermal structure over Gadanki (13.5 N, 79.2 E). Indian J Radio Space Phys 2013, 42(5), 364-70.

There have been several reports on the comparison of daytime mesospheric echoes and their relationship with nighttime thermal structure. In the present work, a few cases are presented in which mesospheric echoes, observed with the MST radar at Gadanki (13.5°N, 79.2°E) during January-February 2011, are compared with temperature information obtained by Sounding of Atmosphere by Broadband Emission Radiometry (SABER) instrument onboard Thermosphere, Ionosphere, Mesosphere Energetics and Dynamics (TIMED) satellite, when there is an overpass near Gadanki close to the time when the echoes are observed. It is found that the mesospheric echoes occur at heights where temperature is minimum or tends to be minimum as compared to the temperature at adjacent heights. The temperature lapse rate decreases below and increases above the height of maximum echoes. This relationship is consistently observed in all the cases considered in the present work. It appears that echoes arise due to change in the refractive index associated with electron density fluctuations caused probably by wave breaking and subsequent turbulence, which could be inferred from the minimum temperature (dynamical cooling) at the height of wave breaking.

3 illus, 22 ref

017011   Sridharan S;Suresh M (NO, National Atmospheric Research Laboratory, Gadanki, Pakala Mandal, Chittoor District-517 112, Email: susridharan@narl.gov.in) : Stratospheric ozone variations over Gadanki (13.5 N, 79.2 E) during january-february 2012 and their relationship with meridional transport near Indian sector. Indian J Radio Space Phys 2013, 42(5), 356-63.

Ozone mixing ratio (OMR) obtained from ozonesondes launched once in a week at Gadanki (13.5°N, 79.2°E) during January-February 2012 showed large variabilities in the stratosphere. On 3 and 10 February 2012, there were large negative and positive percentage changes of ozone with respect to mean OMR within a short period of about a week. It is explained based on potential vorticity (PV) intrusions, which have been considered as dynamic tracer for ozone. The PV map indicated that there was an intrusion of high PV on 3 February 2012 near Indian sector. However, no noticeable intrusion of high PV occurred on 10 February 2012 and the OMR remained almost uniform around 15 ppmv in the tropics in the longitude band of 0°-180°E. The high PV regions correspond to low ozone in the upper stratosphere due to negative latitudinal gradient of ozone. Besides, the height variation of OMR on 13 January 2012 is also explained based on PV intrusions at different pressure levels.

6 illus, 1 table, 8 ref

017010   Solanki R;Singh N;Pant P;Dumka U C;Bhavani Kumar Y;Srivastava A K;Bist S;Chandola H C (NO, Aryabhatta Research Institute of Observational Sciences (ARIES), Manora Peak, Nainital-263 002, Email: narendra@aries.res.in) : Detection of long range transport of aerosols with elevated layers over high altitude station in the Central Himalayas: a case study on 22 and 24 march 2012 at ARIES, Nainital. Indian J Radio Space Phys 2013, 42(5), 332-9.

An advanced version of Boundary Layer LiDAR system, termed as LiDAR for atmospheric measurement and probing (LAMP) has been operational, at Aryabhatta Research Institute of Observational Sciences (ARIES), Nainital, a high altitude station (29.4°N, 79.5°E, <126>1960 m above mean sea level), in central Himalayas, since October 2011. The site is at an altitude, which is well above the planetary boundary layer particularly during the night when observations are taken and thus, lies in the free troposphere. Also, there are no anthropogenic sources of aerosols nearby. However, from March to June, due to strong convection, the aerosols get transported to higher altitudes, up to 2 km or more, from the nearby urban and distant regions as well. Here, a case study of each long range transport and convectively driven elevated aerosol layers, observed with LAMP on 22 and 24 March 2012, has been presented. A normal profile observed on 28 March 2012 without any signature of elevated layer of aerosol is also discussed. The seven days back air mass trajectories over three altitude levels, viz. at 4.5, 3 and 1 km on 22 March; at 4.5, 2 km and 700 m on 24 March, and at 4.5, 2 km and 500 m on 28 March have been derived. The upper levels delineate that the possible origin of the multiple elevated aerosol layers on 22 and 24 March may be transported from far-off regions, such as the dry arid regions of North Africa and Saudi Arabia. To confirm the same, the observations were further substantiated with the TERRA satellite yielded aerosol optical depth (555 nm) obtained from the on board instrument Multi-angle Imaging Spectro Radiometer (MISR), which explicitly shows the high value of time averaged columnar aerosol optical depth (AOD) over Saudi Arabia and Red Sea during 18-23 March 2012 and an appreciable decrease during the period 25-29 March 2012, confirming the origin of long range transport. For the first time, such a high altitude aerosol layers (<126>4.5 km) are observed over this region. The lowest aerosol layer observed on 24 and 28 March 2012 in vertical aerosol backscatter profile is attributed to the transport from adjoining regions via boundary layer evolution and associated mixing.

10 illus, 1 table, 24 ref

017009   Lal D;Chauhan P;Shah R D;Ajai (NO, M.G. Science Institute, Gujarat Univ, Ahmedabad-380 009, Email: prakash@sac.isro.gov.in) : FeO and TiO₂ abundance analysis around apollo-17 landing site using reflectance spectra from the HySI sensor on-board Chandrayaan-1. Curr Sci 2012, 102(11), 1560-4.

The Hyperspectral Imager (HySI) on-board Chandrayaan-1 was used for mineralogical mapping of the lunar surface in the visible and near infrared spectral range. The objective of The study is to investigate the lunar surface composition around the Apollo-17 landing site using the HySI-derived reflectance data and generate elemental abundance maps at higher spatial resolution. In situ data from returned samples along with spectral reflectance band ratios of 950 nm/750 nm and 450 nm/750 nm, normalized by 750 nm reflectance have been used for iron oxide (FeO) and titanium oxide (TiO2) abundance mapping respectively. The HySI-generated FeO and TiO2 maps were further compared with Clementine-derived FeO and TiO₂ maps and found to provide more details on the compositional variability. The regression equation derived using the HySI reflectance data can be used further to map the composition of the physically unsampled lunar surface.

5 illus, 12 ref

017008   Jain A R;Panwar V;Johny C J;Jain S;Peshin S K;Mandal T K;Dhaka S K (NO, CSIR-National Physical Laboratory, Dr K S Krishnan Road, New Delhi-110 012, Email: atmajain@gmail.com) : Tropopause and interchange of minor constituents in the upper troposphere and lower stratosphere (UTLS) region. Indian J Radio Space Phys 2013, 42(5), 320-31.

In this study, an attempt is made to understand the 'freeze drying' process in the tropopause region over India and in associated regions. GPS sonde/radiosonde data collected onboard research vessel Sagar Kanya (SK) and other land stations during two intensive campaigns, namely Bay of Bengal Monsoon Experiment (BOBMEX) and Arabian Monsoon Experiment (ARMEX) have been utilized. In addition, COSMIC/CHAMP satellite data have also been used. It is revealed that on several occasions, low tropopause temperature (<60>191 K) is observed over the ocean as well as on the land stations covering a wide area. During these campaigns, low tropopause temperature and low outgoing long wave radiation (OLR), which is an indicator of convective activity, do not overlap except in few cases of partial overlapping. Observation of low tropopause temperature close to region of convection suggests that the troposphere to stratosphere exchange of water vapour may be affected over these regions. The low tropopause temperature (<60>191 K) are observed to be associated with low water vapour mixing ratio indicating that 'freeze drying' mechanism may be operating over the area of low temperature indicating the significance of convection. In this context, analysis of AURA/MLS data have shown that during the deep convection, water vapour may reach very fast upward up to the tropopause. Another process commonly known as 'subtropical break', which eventually occurs over Indian subcontinent region facilitates the downward transport of minor constituents, such as ozone from lower stratosphere to upper troposphere during winter. SHADOZ network data as well as Indian ozonesonde data provide evidence of downward transport of ozone.

9 illus, 44 ref

017007   Gupta A;Kumar V;Panwar V;Bhatnagar R;Dhaka S K (Physics Dep, Rajdhani College, Delhi Univ, Raja Garden, New Delhi-110 015, Email: anjug123@yahoo.com) : Long term variability in temperature in the upper troposphere and lower stratosphere over Indian and Indonesian region using atmospheric infrared sounder (AIRS) observations. Indian J Radio Space Phys 2013, 42(5), 298-308.

The spatio-temporal patterns and vertical structure of the temperature anomalies, obtained from Atmospheric Infrared Sounder (AIRS), spanning over 9 years (2003-2011) over Indian and Indonesian regions in the upper troposphere and lower stratosphere (UTLS) region, have been examined. An equatorial biennial oscillation with amplitude ranging <126>4-6 K and having a period of <126>24 months was observed in lower stratosphere (LS) from 100 to 50 hPa, whereas it was not seen in the upper troposphere (UT) from 150 to 200 hPa over both the Indian and Indonesian regions. At 50, 70 and 100 hPa, the annual oscillations (AO) with amplitude <126>1-3.5 K were observed near equator in the UT region (at 150 and 200 hPa). However, near subtropics, the nature and amplitude of AO over Indian and Indonesian region was found to be different at different pressure levels. The amplitude of AO at 50 and 70 hPa was larger by <126>1.0-1.5 K over Indonesian region as compared to Indian region. But at 100 and 200 hPa, the amplitude of AO over Indian region was larger by <126>2-3 K, as observed over Indonesian region. It was also observed that the subtropical AO over both the regions was found to be out of phase with the equatorial AO. The subtropical warm temperature anomalies at 100 hPa were found to be typically collocated with subtropical higher values of ozone (using AIRS data) present in the LS. It was also noted that the temperature anomalies at 100 hPa were also found to be anti-correlated with those at 200 hPa.

8 illus, 36 ref

017006   Goel A;Panwar V;Hashiguchi H;Dhaka S K (Radio and Atmospheric Physics Lab, Rajdhani College, Delhi Univ, New Delhi-110 015, Email: vivek_panwar@rish.kyoto-u.ac.jp) : Observed change in association of temperature with solar activity in upper troposphere and lower stratosphere after 1977. Indian J Radio Space Phys 2013, 42(5), 309-19.

This paper presents the analysis of upper tropospheric and lower stratospheric (UTLS) region for the change in the solar dependence of temperature in the last half century, i.e. the second global warming episode. Analysis shows that the solar dependence of temperature at different levels, viz. 500, 300, 200, 100 and 50 mb has abruptly changed after 1977. The change is recorded around the world in UTLS region with its irrefutable prominence around the tropopause (near 100 mb pressure level or 16 km height over equator and 250 mb pressure level or 10 km height over the poles). The abrupt and continuous increase in number of El Nino events, after 1977 as compared to the number of La Nina events, is examined with other global phenomenon, such as global warming, ozone depletion, polar vortex and increase in greenhouse gases to be a probable mechanism triggering this change. Observations indicate that it is actually the change in solar dependence of temperature that leads to the global warming.

6 illus, 5 tables, 33 ref

017005   Bhatnagar R;Panwar V;Shibagaki Y;Hashiguchi H;Fukao S;Kozu T;Takahashi M;Dhaka S K (Radio and Atmospheric Physics Lab, Physics Dep, Rajdhani College, Delhi Univ, New Delhi-110 015, Email: rangoli_b@rediffmail.com) : Hourly radiosonde observation of humidity and temperature and high resolution vertical wind using the equatorial atmosphere radar during convection over Koto Tabang, Indonesia in CPEA-II campaign. Indian J Radio Space Phys 2013, 42(5), 277-91.

Distinct wave perturbations for <126> 2-3 hours were observed during Coupling Processes in Equatorial Atmosphere-II in temperature and vertical wind in the tropopause region (<126>17-19 km) using hourly radiosonde launchings and high resolution Equatorial Atmosphere Radar observations, respectively over Koto Tabang (100.32°E, 0.20°S) during active convective events. Perturbations in temperature and humidity were found to be strongly anti-correlated in the upper troposphere and lower stratosphere region. Observations suggest that convective storm had increased humidity by a factor of 3-5 in the middle and upper troposphere (water vapour mixing ratio were also increased over convective period); gravity waves were generated near and above tropopause, which were not detected during no-convection period. Hourly temperature observations, which have covered complete life cycle of two convective storms of 7-8 hours, showed a significant enhancement in water vapour mixing ratio up to <126>15-16 km height that corresponds to a level of strong wind shear existing below tropopause. There is a significant decrease in temperature around this level of strong wind shear.

10 illus, 2 tables, 24 ref

015951   Mishra R;Sudhakar M (NO, National Centre for Antarctic and Ocean Research, Headlnad Sada, Vasco, Goa-403 804, Email: ravimishra@ncaor.org) : Recovery of the GSLV debris from the shallow waters of the bay of Bengal, off Sriharikota, Andhra Pradesh, India. Curr Sci 2012, 102(2), 314-9.

The Geosynchronous Satellite Launch Vehicle (GSLV) launched from SHAR, Sriharikota on 10 July 2006 fell into the Bay of Bengal due to failure of the first stage L-40 engine. Search for recovering strap on engine(s) for conducting failure analysis was undertaken. Sugar Kanya, Sugar Purvi and Sagur Puschimi - the vessels of the Ministry of Earth Sciences, Government of India, and Akademik Boris Petrov, a research vessel that was hired, were deployed in search and recovery operations. Methods adopted for search were swath bathy-metric surveys, side scan sonar surveys, underwater videography and search by remotely operated vehicles. Divers guided by survey results, recovered three engines and parts of a fourth engine within 100 days of the mishap from 10 to 30 m depth in the Bay of Bengal.

3 illus, 3 tables, 10 ref

015040   Sivarani T (NO, Indian Institute of Astrophysics, II Block Kormangala, Bangalore-560 034, Email: sivarani@iiap.res.in) : Stellar relics from the early galaxy. J Astrophys Astr 2013, 34(1), 5-17.

Reviewed the recent progress in the field of stellar/galactic archeology, which is a study of the relics from the early galaxy. The oldest and most pristine objects that can be observed in the galaxy are the low mass metal poor stars of the Milky Way. They were formed during the early phases, when the ISM might have been polluted only by the Pop-Ill supernovae. With the recent large spectroscopic surveys (e.g. HK survey by Beers and collaborators, the Hamburg-ESO survey by Christlieb and collaborators and Sloan Digital Sky Survey) it has been possible to get clues on the nature of the first stars that has contributed to the heavy elements. Most of these metal-poor low mass stars also retain their signature of the early dynamical evolution of the galaxy, which can be studied through their orbits around the galaxy and spatial distribution. Discussed the connection between the chemical and the kinematical properties of metal-poor stars in order to probe the early galaxy formation. Also discuss about the globular clusters, the satellite galaxies around the Milky Way and its possible contribution to the formation of the galaxy halo.

7 illus, 45 ref

015039   Singh K P (NO, Tata Institute of Fundamental Research, Homi Bhabha Road, Mumbai-400 005) : X-ray view of quasars. Bull Astr Soc India 2013, 41(2), 137-57.

Presented an overview of observational studies of quasars of all types, with particular emphasis on X-ray observational studies. The presentation is based on the most popularly accepted unified picture of quasars - collectively referred to as AGN (active galactic nuclei) in this review. Characteristics of X-ray spectra and X-ray variability obtained from various X-ray satellites over the last 5 decades have been presented and discussed. The contribution of AGN in understanding the cosmic X-ray background is discussed very briefly. Attempt has been made to provide up-to-date information; however, this is a vast subject and this presentation is not intended to be comprehensive.

6 illus, 111 ref

015038   Shanti Priya D;Sriram K;Shaju K Y;Vivekananda Rao P (Astronomy Dep, Osmania Univ, Hyderabad-500 007, Email: astroshanti@gmail.com) : Photometric study of hot contant binaries in SMC. Bull Astr Soc India 2013, 41(2), 159-72.

Authors present the analysis of twenty hot contact binary systems in the Small Magellanic Cloud using the Wilson-Devinney method and their properties are discussed in context of TRO model.

8 illus, 8 tables, 40 ref

015037   Prakasam K S;Rai S R;Meena G S (NO, National Geophysical Research Institute (CSIR), Hyderabad-500 007, Email: ksprakasam@ngri.res.in) : Seismic signatures of the sonic boom during the launch of Chandrayaan-1. Curr Sci 2012, 102(1), 105-9.

This article present the seismic signatures generated by the sonic boom during the launch of Chandrayaan-1 from the Satish Dhawan Space Centre, Sriharikota on 22 October 2008. A network of six digital broadband seismographs spread over a distance of 35 km recorded the air coupled seismic waves due to the sonic boom. These are recorded as first arriving waves on the seismogram with a velocity of about 338 m/s and frequency of <126> 5 Hz. Also, the amplitudes of the waveforms indicate a high attenuation of the order of 10 in the marshy Pulicat Lake area. The lake area experienced a significant pressure of about 55 microbar due to the impact of the sonic boom.

6 illus, 2 tables, 15 ref

015036   Pathania A;Lal A K;Mohan C (NO, School of Mathematics and Computer Applications, Thapar Univ, Patiala-147 004, Email: ankush.pathania@gmail.com) : On the use of roche equipotentials in analysing the problems of binary and rotating stars. J Astrophys Astr 2013, 34(1), 69-73.

Kopal introduced the concept of Roche equipotentials to analyse the effects of rotational and tidal distortions in case of stars in binary systems. In this approach a mathematical expression for the potential of a star in a binary system is obtained by approximating its inner structure with Roche model. This expression for the potential has been used in subsequent analysis by various authors to analyse the problems of structures and oscillations of synchronous and nonsynchronus binary stars as well as single rotating stars. Occasionally, doubts have been expressed regarding the validity of the use of this approach for analysing nonsynchronous binaries and rota-tionally and tidally distorted single stars. In this paper we have tried to clarify these doubts.

1 illus, 14 ref

015035   Pandey C P;Goswami U D;Dehnen H;Bisht S (Physics Dep, Kumaun Univ, Nainital-263 001, Email: chhavi.pandey@gmail.com) : Anharmonic vibrations in pulsating stars. Indian J Phys 2012, 86(9), 849-53.

Studied the anharmonic vibrations in pulsating stars using the Hamiltonian formulation of Newtonian dynamics. We have considered the spherical and homogeneous stars as simple case which can however put a constraint on the model in a generalized sense. Utilizing the equation of motion, it has been found that the theoretical model investigated in this study could produce the anharmonic nature of pulsations in radial velocity, luminosity and apparent magnitude with respect to time. We could improve the understanding of such anharmonic pulsation at theoretical front in comparison to the already existing models. However, there is still a large discrepancy in between the observed data and calculated values for the known anharmonic ally pulsating star (viz., δ Cepheid).

1 illus, 7 ref

015034   Ojha R (NO, NASA/Goddard Space Flight Center, Code 661, Astroparticle Physics Labo, Greenbelt, MD 20770, U.S.A, Email: roopesh.ojha@nasa.gov) : Parsec-scale structure of quasars: dawn of the golden age?. Bull Astr Soc India 2013, 41(2), 117-36.

Half a century after their discovery, the study of quasars remains one of the most fascinating intellectual challenges in astronomy. Quasars are laboratories for everything from relativity to magnetohydrodynamics and are perhaps the best available probes for cosmology. A tremendous amount has been learned about quasars and yet many of the most fundamental questions about their physics remain open. Parsec-scale observations have played an indispensable role in building up our current understanding of quasars; virtually everything we know about quasars depends on such observations. However, the finest hour for parsec scale observations may be just beginning. This is partly due to the development of highly reliable VLBI networks (which is continuing) but mostly due to the unprecedented availability of multiepoch, simultaneous, broadband observations that have long been the 'holy grail' for quasar researchers.

3 illus, 112 ref

015033   Kjurkchieva D P;Dimitrov D P;Ibryamov S I; Srinivasa Rao M (Astronomy Dep, Shumen Univ, 115 Universitetska Str., 9712, Shumen, Bulgaria, Email: dinko@astro.bas.bg) : GSC 2701-2527, a new multiperiodic high-amplitude delta scuti variable. Bull Astr Soc India 2013, 41(2), 173-82.

The photometric observations reveal that GSC 2701-2527 is a high-amplitude 5 Scuti star with quite low temperature. The frequency analysis exhibits that it is multiperiodic pulsator. The obtained period ratio f₁f₂=0.791 is higher than the canonical value. The large value of the period ratio f₁/f₃=0.813 implies nonradial nature of the third mode. Using empirical relations for the δ Scuti stars we determined the global parameters of GSC 2701-2527.

6 illus, 2 tables, 31 ref

015032   Jana P K;Goswami S;Midya S K (Chemistry Dep, Government College of Education, Banipur, North-24 Parganas-743 233, West Bengal, Email: pkjjngl@yahoo.co.in) : Relation between tropospheric and stratospheric ozone at Thumba (8.5°N, 77°E) and Bangalore (13°N, 77.5°E), India and its effect on environment. Indian J Phys 2012, 86(9), 769-75.

Presents the nature of long-term seasonal and yearly variations of tropospheric and stratospheric ozone over Thumba (8.5°N, 77°E) and Bangalore (13°N, 77.5°E), India. Seasonal variations clearly reveal that stratospheric ozone concentration attained comparatively higher value in the months from July to September while lower tropospheric ozone concentration at the same time over the above stations during the period 1979-2005. Yearly variation shows increasing trend in tropospheric ozone but decreasing trend in stratospheric ozone from 1979 to 2005. Undesirable environmental effects due to such tropospheric rise and stratospheric decline in ozone are also mentioned.

4 illus, 52 ref

015031   El-Nabulsi A R (NO, Key Laboratory of Numerical Simulation of Sichuan Province, Neijing-641 112, Sichuan, China, Email: nabulsiahmadrami@yahoo.fr) : New astrophysical aspects from Yukawa fractional potential correction to the gravitational potential in D dimensions. Indian J Phys 2012, 86(9), 763-8.

The aim of this paper is to generalize in D - d + 1 the Newtonian gravity by adding to the gravitational potential for fractal distribution of particles within the linearized theory, a propagating fractional correctional mode which have the form of Yukawa (exponential) fractional potential. Exact solutions of Einstein field equations are presented where many interested features are derived and discussed in some details.

34 ref

015030   Das M (NO, Indian Institute of Astrophysics, II Block, Koramangala, Bangalore-560 034, Email: mousumi@iias.res.in) : Giant low surface brightness galaxies: evolution in isolation. J Astrophys Astr 2013, 34(1), 19-31.

Giant Low Surface Brightness (GLSB) galaxies are amongst the most massive spiral galaxies that know of in our Universe. Although they fall in the class of late type spiral galaxies, their properties are far more extreme. They have very faint stellar disks that are extremely rich in neutral hydrogen gas but low in star formation and hence low in surface brightness. They often have bright bulges that are similar to those found in early type galaxies. The bulges can host low luminosity Active Galactic Nuclei (AGN) that have relatively low mass black holes. GLSB galaxies are usually isolated systems and are rarely found to be interacting with other galaxies. In fact many GLSB galaxies are found under dense regions close to the edges of voids. These galaxies have very massive dark matter halos that also contribute to their stability and lack of evolution. In this paper we briefly review the properties of this unique class of galaxies and conclude that both their isolation and their massive dark matter halos have led to the low star formation rates and the slower rate of evolution in these galaxies.

2 illus, 2 tables, 92 ref

015029   Chauhan P;Prabhjot Kaur;Srivastava N; Bhattacharya S;Ajai;Kiran Kumar A S;Goswami J N (NO, Space Applications Centre (ISRO), Jodhpur Tekra, Ahmedabad-380 015, Email: prakash@sac.isro.gov.in) : Compositional and morphological analysis of high resolution remote sensing data over central peak of tycho crater on the moon: implications for understanding lunar interior. Curr Sci 2012, 102(7), 1041-6.

Tycho is a young impact crater of Copernican age (approx 110 Ma) in the southern highlands of the Moon. The crater has a well-developed central peak with an altitude of approx 2 km. Central peaks of large lunar craters are ideal to study the deep-seated crustal material. In this study authors report the results of an integrated morphological and compositional analysis for the central peak of the Tycho crater by using high-resolution data from Terrain Mapping Camera (TMC) and Moon Mineralogy Mapper (M3) on-board Chandrayaan-1 along with data from Narrow Angle Camera (NAC) of Lunar Reconnaissance Orbiter. The analysis shows various morphological features associated with valcanism in the form of volcanic vents, domes, clasts, impact melt lava ponds showing distinct cooling cracks, and flow patterns on and around this central peak. Compositionally, M3 data suggest that the central peak is highly heterogeneous and dominated by high-Ca pyroxene-rich rocks. The base of the central peak is anorthositic in nature. These new morphological and mineralogical evidences suggest that the central peak of the Tycho crater has diverse morphology and mineralogical variability, suggesting multiphase modifications subsequent to the crater formation. The presence of diverse mafic lithologies on the central peak situated, in a predominantly anorthositic geological setting, suggests exposure of the subsurface pluton during the impact and thus provides insight into the composition of the lunar inner crust.

6 illus, 24 ref

015028   Arya A S;Rajasekhar R P;Thangjam G;Gujrati A; Amitabh;Trivedi S;Gopala Krishna B;Ajai;Kiran Kumar A S (NO, Space Applications Centre Indian Space Research Organization, Ahmedabad-380 015, Email: arya_as@sac.isro.gov.in) : Lunar surface age determination using chandrayaan-1 TMC data. Curr Sci 2012, 102(5), 783-8.

Surface age determination is quintessential for understanding and to reconstruct the geo-chronology of any planetary body. The chronology and stratigraphic reconstruction of terrestrial rocks is accomplished by way of radiometric dating, index fossils, lithostratigraphic correlation, etc. However, in the case of remote planetary bodies, with little accessibility to their rock samples, the Crater Size Frequency Distribution (CSFD)) is a well developed method for determining surface ages using remote sensing techniques. India moon mission, Chandrayaan-I carried a Terrain Mapping Camera (TMC) having high spatial resolution (5 m) and stereo viewing. In the present study, the TMC datasets have been utilized for lunar surface age dating using CSFD and comparing with the radiometrically derived ages of the samples returned by Apollo missions, followed by extension of the same technique for other mare basins, the Copernicus crater and correlating the cratering events in the Taurus-Littrow valley with the Tycho event.

7 illus, 14 ref

015027   Alhassan J A;Ubachukwu A A;Odo F C (Physics & Astronomy Dep, Nigeria Univ, Nsukka, Nigeria, Email: jibrinalhassan2002@yahoo.com) : On the absence of core luminosity-core-dominance parameter (P_c-R0 correlation in radio galaxies and BL lacs. J Astrophys Astr 2013, 34(1), 61-7.

Presented an alternative interpretation for the absence of correlation in the relationship between the core radio power (Pc) and core-dominance parameter (R) for a sample of BL Lacs and radio galaxies found in Fan & Zhang (Astron. Astrophys. 407, 899 (2003))'. This is contrary to the predictions of the relativistic beaming and radio source orientation models in which the core luminosity is expected to be Doppler-boosted relative to the extended luminosity which is generally assumed to be isotropic. Our analysis of the PC - R data indicates a strong luminosity selection effect (reminiscent of bright source samples due to Malmquist bias) in the sample. In particular, authors showed that a strong PC - R correlation exists above some redshift cut-off which may correspond to the flux limit of the sample used.

2 illus, 22 ref

013815   Ronander E;Strydom H J;Botha L R (NO, Klydon (Pty) Ltd., P.O. Box 1552, Pretoria, South Africa, Email: rinar.ronander@klydon,co.za) : High-pressure continously tunable CO₂ lasers and molecular laser isotope separation. Pramana J Phys 2014, 82(1), 49-58.

The acronym MLIS (molecular laser isotope separation) defines the laser process whereby the isotopes of uranium can be separated by mid-infrared laser/s when the molecule employed is UF₆. The theoretical and spectroscopical data to configure and enable experiments and demonstrations in the laboratory is adequate. However, the engineering and commercial aspects require innovative technology solutions that are not presently available in the literature on these topics. This paper is an overview of the most salient features of MLIS and its potential utility at an industrial level.

8 illus, 9 ref

013814   Anand A;Vora P;Mahajan S;Trivedi V;Chhaniwal V;Singh A;Leitgeb R;Javidi B (Applied Physics Dep, Faculty of Technology and Engineering M.S. Baroda Univ, Vadodara-390 001, Email: arun_nair_in@yahoo.com) : Compact, common path quantitative phase microscopic techniques for imaging cell dynamics. Pramana J Phys 2014, 82(1), 71-8.

Microscopy using visible electromagnetic radiation can be used to investigate living cells in various environments. But bright field microscopy only provides two-dimensional (2D) intensity distribution at a single object plane. One of the ways to retrieve object height/thickness information is to employ quantitative phase microscopic (QPM) techniques. Interferometric QPM techniques are widely used for this. Digital holographic microscopy (DHM) is one of the state-of-the-art methods for quantitative three-dimensional (3D) imaging. Usually it is implemented in two-beam geometry, which is prone to mechanical vibrations. But to study dynamics of objects like red blood cells, one needs temporal stability much better than the fluctuations of the object, which the two-beam geometry fails to deliver. One way to overcome this hurdle is to use self-referencing techniques, in which a portion of the object beam will act as the reference beam. Here the development of self-referencing QPM techniques is described along with the results.

4 illus, 27 ref

012805   Rathore B S;Kaushik S C;Bhadoria R S;Parashar K K;Gupta D C (NO, School of Studies in Physics, Jiwaji Univ, Vidya Vihar, Gwalior-474 011, Email: balveer_singhra@yahoo.co.in) : Sunspots and geomagnetic storms during solar cycle-23. Indian J Phys 2012, 86(7), 563-7.

Geo-magnetic storms generally occur due to abnormal conditions in the interplanetary magnetic field (IMF) and solar wind plasma emissions caused by various solar activities. The Disturbance storm time (Dst) index is used to identify more than 220 storms which occurred in time interval 1996-2007, the span of solar cycle-23. Using the minimum Dst value as an indicator, we classify the storms as moderate (138), strong (67), severe (11), and great (4). We have analyzed and studied them statistically and have found that yearly occurrences of geomagnetic storm are strongly correlated with 11 year sunspot cycle, but no significant correlation between the maximum and minimum phase of solar cycle-23 has been found. It is also found that solar cycle-23 is remarkable for occurrence of intense geomagnetic storms during its declining phase. It is also observed that Halo CME is the main cause to produce geomagnetic storms. The results are discussed in the present paper.

4 illus, 1 table, 22 ref