We present a new Bayesian non-parametric deprojection algorithm DOPING (Deprojection of Observed Photometry using and INverse Gambit), that is designed to extract 3-D luminosity density distributions...
Comparing X-ray and Dynamical Mass Profiles in the Early-Type Galaxy NGC 4636 (2009)
Johnson, Ria, Chakrabarty, Dalia, O'Sullivan, Ewan, Raychaudhury, Somak
We present the results of an X-ray mass analysis of the early-type galaxy NGC 4636, using Chandra data. We have compared the X-ray mass density profile with that derived from a dynamical analysis of...
Warps and Bars from the External Tidal Torques of Tumbling Dark Halos (2009)
Dubinski, John, Chakrabarty, Dalia
The dark matter halos in $\Lambda$CDM cosmological simulations are triaxial and highly flattened. In many cases, these triaxial equilibria are also tumbling slowly, typically about their short axes,...
CHASSIS - Inverse Modelling of Relaxed Dynamical Systems (2009)
The state of a non-relativistic gravitational dynamical system is known at any time $t$ if the dynamical rule, i.e. Newton's equations of motion, can be solved; this requires specification of the...
Total mass distributions of Sersic galaxies from photometry $&$ cent\ ral velocity dispersion (2009)
Chakrabarty, Dalia, Jackson, Brendan
We develop a novel way of finding total mass density profiles in Sersic ellipticals, to about 3 times the major axis effective radius, using no other information other than what is typically...
Cluster Geometry & Inclinations from Deprojection Uncertainties (2008)
Chakrabarty, Dalia, De Filippis, Elisabetta, Russell, Helen
{The determination of cluster masses is a complex problem that would be aided by information about the cluster shape and orientation (along the line-of-sight).} {It is in this context, that we have...
Quantifying Chaos in Models of the Solar Neighbourhood (2008)
Chakrabarty, Dalia, Sideris, Ioannis V.
{} {To quantify the amount of chaos that exists in the local phase space.} {A sample of orbits from four different models of the Solar neighbourhood phase space are analysed by a new chaos...
The Distribution of Dark Matter in the Halo of the early-type galaxy NGC 4636 (2008)
Chakrabarty, Dalia, Raychaudhury, Somak
We present the density structure of dark matter in the outer parts (to about 7 effective radii) of the elliptical galaxy NGC 4636, from the radial velocities of 174 globular clusters, using the...
Local Phase Space - Shaped by Chaos? (2008)
We attempt to understand the state of the local phase space by comparing simulated 2-D velocity distributions to the distribution that is constructed for the solar neighbourhood, from measurements of...
DOPING: a New Non-parametric Deprojection Scheme (2008)
Chakrabarty, Dalia, Ferrarese, Laura
We present a new non-parametric deprojection algorithm DOPING (Deprojection of Observed Photometry using and INverse Gambit), that is designed to extract the three dimensional luminosity density...
Phase Space Structure in the Solar Neighbourhood (2007)
We examine the idea that dynamical parameters can be estimated by identifying locations in the solar neighbourhood where simulated velocity distributions match the observed local distribution. Here,...
Mass Modelling with Minimum Kinematic Information (2007)
Mass modelling of early-type systems is a thorny issue. In this paper, we present a new mass modelling formalism for ellipticals that invokes no observations other than the central velocity...
An Inverse Look at the Center of M15 (2006)
The observed radial and transverse velocities of individual stars in M15 are implemented as inputs to a fully non-parametric code (CHASSIS) in order to estimate the equilibrium stellar distribution...
An Inverse Problem Approach to Cluster Dynamics (2004)
Chakrabarty, Dalia, Zwart, Simon Portegies
We propose a new non-parametric algorithm that can be implemented to study and characterize stellar clusters. The scheme attempts to simultaneously recover the stellar distribution function and the...
Patterns in the Outer Parts of Galactic Disks (2004)
This paper describes test particle simulations of the response of the outer parts of Galactic disks to barring and spiral structure. Simulations are conducted for cold Mestel disks and warm...
Magnetically warped discs in close binaries (2002)
Murray, James, Chakrabarty, Dalia, Wynn, Graham, Kramer, Louisa
We demonstrate that measurable vertical structure can be excited in the accretion disc of a close binary system by a dipolar magnetic field centred on the secondary star. We present the first high...
A Non-Parametric Estimate of the Mass of the Central Black Hole in the Galaxy (2001)
Chakrabarty, Dalia, Saha, Prasenjit
We estimate the mass of the central black hole in our Galaxy from stellar kinematical data published by Ghez et al. (1998) and Genzel et al. (2000). For this we develop a method, related to Merritt...