Sample Request for Visitor Program

1. STScI Proposer: R. Black
Co-Investigator: R. Green, R. White

2. Name of proposed visitor: Dr. Ima Visitor

Institution : European Southern Observatory,
Garching bei Munchen, Germany

Visitor's e-mail address: ImaVisitor@eso.org

3. Dates of proposed visit: Nov 16 - Dec 7, 2004

4. Length of visit: 3 weeks

5. Likelihood of visit: definite

6. Estimated expenses:

* Travel [round trip Munich - BWI/Dulles] : $ 1000
* Lodging [3 nights @ $85 Broadview]: $ 255
* Meals [3 days x max 25 daily rate] : $ 75
* Other [taxis] : $ 60

SUBTOTAL: $ 1390

Less cost sharing, if any: $ 1000

TOTAL REQUEST: $ 390

7. Notes on expenses [e.g., source of cost sharing, explanation of "Other" items, etc.]:

The European Southern Observatory (ESO) will pay for the airfare. We are requesting support for lodging expenses and local transportation.

8. Non-technical description of the visit :

Dr. Visitor is a post-doctoral research Fellow at the ESO Headquarters near Munich, Germany. She has ongoing scientific collaborations with STScI staff members Black, White, and Brown. She will visit STScI from Nov 16 - Dec 7, 2003 to work with Black, White, and Brown on these projects, as described below.

This visit is not to work as co-I or PI with Institute scientists on a related HST GO/AR/HF grant.

9. Technical scientific justification:

Visitor will work with Black and White on a theoretical project to constrain the origin of the nuclear gas velocity dispersion in nearby ellipticals. Conventional dynamical modeling of gas disks to determine central black hole masses in ellipticals assumes a collisionless gas residing in circular orbits. These models have generally been found to underpredict the observed velocity dispersions in real data. This, in turn, might invalidate the black hole mass determinations inferred from such models. Visitor will explore both a gravitational and non-gravitational origin for the excess gas dispersion. To explore a gravitational origin, we will extend our modeling software to include non-thin-disk configurations for the gas. To explore a non-gravitational origin, we will analyze results from hydrodynamical modeling of central gas in galaxies kindly provided to us by Keiichi Wada. The goal is to simulate spectroscopic observations of these hydrodynamical models, which might provide insight into methods for interpre ting actual observations.

Visitor will also work with White and Brown on the analysis of radio data obtained with the Westerbork Synthesis Radio Telescope (WSRT) of three ellipticals with radio cores. The radio cores in these ellipticals might represent the pre- or postcursors of a radio-loud phase in which the ellipticals have extended radio-jets. The WSRT deep 21cm imaging is aimed at detecting low-level jet emission from relic radio-jets and lobes. In combination with archival optical data, we hope to constrain the triggering mechanism and evolutionary path of radio-loud activity in these ellipticals.

(Latest revision: 23 February 2005)