Orbital parameters of binary radio pulsars in globular clusters and stellar interactions (2009)
The observed distribution of globular cluster binary radio pulsars in the eccentricity versus orbital period plane can be explained as a result of binary-single star interactions. Our numerical and...
Gopakumar, Achamveedu, Bagchi, Manjari, Ray, Alak
We investigate the observational signatures associated with one of the proposed formation scenario for the recently discovered highly eccentric binary millisecond pulsar (MSP) PSR J1903+0327 in the...
Massive stars as thermonuclear reactors and their explosions following core collapse (2009)
Nuclear reactions transform atomic nuclei inside stars. This is the process of stellar nucleosynthesis. The basic concepts of determining nuclear reaction rates inside stars are reviewed. How stars...
High sensitivity searches of globular clusters (GC) for radio pulsars by improved pulsar search algorithms and sustained pulsar timing observations have so far yielded some 140 pulsars in more than...
X-rays from the explosion site: Fifteen years of light curves of SN 1993J (2009)
Chandra, Poonam, Dwarkadas, Vikram V., Ray, Alak, Immler, Stefan, Pooley, David
We present a comprehensive analysis of the X-ray light curves of SN 1993J in a nearby galaxy M81. This is the only supernova other than SN 1987A, which is so extensively followed in the X-ray bands....
Eleven Years of Radio Monitoring of the type IIn Supernova SN 1995N (2009)
Chandra, Poonam, Stockdale, Christopher J., Chevalier, Roger A., Van Dyk, Schuyler D., Ray, Alak, Kelley, Matthew T., ...
We present radio observations of the optically bright Type IIn supernova SN 1995N. We observed the SN at radio wavelengths with the Very Large Array for 11 years. We also observed it at low radio...
We analyze the observed distribution of the orbital eccentricity and period of binary radio pulsars in globular clusters using computational tools to simulate binary-single star interactions....
Eleven years of radio monitoring of the Type IIn supernova SN 1995N (2008)
Chandra, Poonam, Stockdale, Christopher J., Chevalier, Roger A., Van Dyk, Schuyler D., Ray, Alak, Kelley, Matthew T., ...
We present radio observations of the optically bright Type IIn supernova SN 1995N. We observed the SN at radio wavelengths with the Very Large Array (VLA) for 11 years. We also observed it at low...
Chandra's Tryst with SN 1995N (2005)
Chandra, Poonam, Ray, Alak, Schlegel, Eric M, Sutaria, Firoza K, Pietsch, Wolfgang
We present the spectroscopic and imaging analysis of Type IIn supernova SN 1995N observed with the Chandra X-Ray Observatory on 2004 March 27.We compare the spectrum obtained from our Chandra...
Chandra's tryst with SN 1995N (2005)
Chandra, Poonam, Ray, Alak, Schlegel, Eric M., Sutaria, Firoza K., Pietsch, Wolfgang
We present the spectroscopic and imaging analysis of a type IIn supernova SN 1995N observed with the Chandra X-ray observatory on 2004 March 27. We compare the spectrum obtained from our Chandra...
Chandra's tryst with SN 1995N (2005)
Chandra, Poonam, Ray, Alak, Schlegel, Eric M., Sutaria, Firoza K., Pietsch, Wolfgang
Chandra's Tryst with SN 1995N (2005)
Chandra, Poonam, Ray, Alak, Schlegel, Eric M, Sutaria, Firoza K, Pietsch, Wolfgang
We present the spectroscopic and imaging analysis of Type IIn supernova SN 1995N observed with the Chandra X-Ray Observatory on 2004 March 27.We compare the spectrum obtained from our Chandra...
Baby supernovae through the looking glass at long wavelengths (2004)
We emphasize the importance of observations of young supernovae in wide radio band. We argue on the basis of observational results that only high or only low frequency data is not sufficient to get...
Implications of aging in young supernovae (2004)
We present here the combined radio spectrum from the Giant Metrewave Radio Telescope (GMRT) and Very Large Array (VLA) of type-IIb SN 1993J (age 11 years) and a type-Ic SN 2003bg (age 1 year). In SN...
Synchrotron aging and the radio spectrum of SN 1993J (2004)
Chandra, Poonam, Ray, Alak, Bhatnagar, Sanjay
We combine the GMRT low frequency radio observations of SN 1993J with the VLA high frequency radio data to get a near simultaneous spectrum around day 3200 since explosion. The low frequency...
Synchrotron aging and the radio spectrum of SN 1993J (2004)
Chandra, Poonam, Ray, Alak, Bhatnagar, Sanjay
We combine the GMRT low frequency radio observations of SN 1993J with the VLA high frequency radio data to get a near simultaneous spectrum around day 3200 since explosion. The low frequency...
Synchrotron aging and the radio spectrum of SN 1993J (2004)
Chandra, Poonam, Ray, Alak, Bhatnagar, Sanjay
We combine the GMRT low frequency radio observations of SN 1993J with the VLA high frequency radio data to get a near simultaneous spectrum around day 3200 since explosion. The low frequency...
Radio Studies of Young Core Collapse Supernovae (2002)
Chandra, Poonam, Ray, Alak, Bhatnagar, Sanjay
Multi-frequency observations of two radio bright SNe (SN1993J, SN1979C) carried out over a year with GMRT are presented. Their radio light curves trace the evolution of the mass loss in the stellar...
Deep optical observations at the position of PSR1706-44 with the VLT-UT1 (1998)
Lundqvist, Peter, Sollerman, Jesper, Ray, Alak, Leibundgut, Bruno, Sutaria, Firoza
We present optical data gathered by the VLT Test Camera in the V-band at the radio (interferometric) position of PSR1706-44. We find no optical counterpart to the pulsar in the VLT image. At a...
Oscillation Effects On Neutrinos From The Early Phase Of a Nearby Supernova (1998)
Majumdar, Debasish, Kar, Kamales, Ray, Alak, Raychaudhuri, Amitava, Sutaria, Firoza K.
Neutrinos emitted during stellar core collapse leading to a supernova are primarily of the electron neutrino type at source which may undergo oscillation between flavor eigenstates during propagation...
Thermal conduction and cooling of young neutrons stars. Evolution of pulsar magnetic fields / (1979)
Thesis (Ph. D.)--Columbia University, 1979.