Testimony of Chai R. Feldblum

Testimony of Chai R. Feldblum, for What An Aging Workforce Can Teach Us About Workplace Flexibility July 18, 2005

Off-vertical rotation - A convenient precise means of exposing the passive human subject to a rotating linear acceleration vector

Disturbances of vestibular origin comprising motion sickness resulting from rotating tilted chai

X-ray detection of the substellar twin 2MASS J11011926-7732383 AB

2MASS J11011926-7732383 AB (hereafter 2M1101AB), located in the Cha I star forming region, is a rare wide-separation brown dwarf binary. XMM-Newton and Chandra observations of 2M1101AB have allowed us to examine the influence of physical parameters (mass, bolometric luminosity and effective temperature) on X-ray emission from a coeval pair of substellar objects. The spatial resolution of XMM-Newton is not sufficient to separate contributions from the two components in the binary. The X-ray source detected with XMM-Newton has a column density compatible with the infrared extinction of component A. On the other hand, the binary is resolved with Chandra, and the bulk of the X-ray emission is clearly associated with the photospherically cooler component B. These apparently contradictory results point at strong variability of 2M1101's X-ray emission. Combined with previous sensitive X-ray observations from low-mass members of ChaI, we find a decline of X-ray luminosity with decreasing (sub)stellar mass that is typical for star forming regions. 2M1101B is the coolest (spectral type M8.25) and least massive brown dwarf of ChaI detected in X-rays so far. It is also among the youngest (~1 Myr) substellar ChaI members, and therefore relatively luminous. Most bona fide brown dwarfs of Cha I have remained below the sensitivity limits of available X-ray observations, because of their low luminosity associated with higher age.Comment: accepted for publication in Astronomy & Astrophysic

A fluffy friend can chase stress away

With final exams looming, VCU students could play with friendly dogs at “Paws for Stress” events held by the Center for Human-Animal Interaction and University Counseling services. CHAI is studying whether interacting with therapy dogs really can lower your stress levels

Chai's Conjecture and Fubini properties of dimensional motivic integration

We prove that a conjecture of Chai on the additivity of the base change conductor for semi-abelian varieties over a discretely valued field is equivalent to a Fubini property for the dimensions of certain motivic integrals. We prove this Fubini property when the valued field has characteristic zero.Comment: 22 page