Bulletin of the American Physical Society
Annual Meeting of the Four Corners Section of the APS
Volume 59, Number 11
Friday–Saturday, October 17–18, 2014; Orem, Utah
Session B6: Planets and Star Formation |
Hide Abstracts |
Chair: Karl Haisch, Utah Valley University Room: Science Building 280 |
Friday, October 17, 2014 10:15AM - 10:39AM |
B6.00001: The Lunar Environment Invited Speaker: Mihaly Horanyi This talk will summarize the recent results from Lunar The Lunar Dust Experiment (LDEX) onboard the Lunar Atmosphere and Dust Environment Explorer (LADEE) mission. LDEX discovered a permanently present dust cloud engulfing the Moon. The cloud is non-spherical, showing higher densities in a direction canted towards the Sun from the lunar orbital motion. The size, velocity, and density distributions of the dust particles are consistent with ejecta clouds generated from the continual bombardment of the lunar surface by sporadic interplanetary dust particles. Intermittent density enhancements were observed during several of the annual meteoroid streams, especially during the Geminids. LDEX found no evidence of the suspected density enhancements over the terminators where electrostatic processes were predicted to efficiently loft small grains. The talk will conclude by summarizing our current understanding of the interactions of the solar wind plasma flow and UV radiation with the lunar surface, and the possible generalization to other airless bodies in the solar system. [Preview Abstract] |
Friday, October 17, 2014 10:39AM - 10:51AM |
B6.00002: Atmosphere of a Transiting Hot-Jupiter System, Probed in the Lyman-alpha Band Louis Oberto, Zheng Zheng A Jupiter-like extrasolar planet (i.e., a hot-Jupiter), close to the host star, can have an atmosphere extending to several times the planet radius, as a result of heating from the star. Such an extended atmosphere is transparent to visible light and hard to be observed in the optical band. However, in the Lyman-$\alpha$ band, the extended atmosphere can be detected, because of the interaction of Lyman-$\alpha$ photons with the neutral hydrogen atoms in the atmosphere. A fraction of the Lyman-$\alpha$ photons emitted from the star are intercepted by the planet, and these photons experience resonant scattering in the planet's atmosphere and eventually escape the atmosphere. Therefore, in the Lyman-$\alpha$ band, the planet appears to be effectively emitting light. We perform a Lyman-$\alpha$ radiative transfer study of a model transiting hot-Jupiter system. In the Lyman-$\alpha$ band, the transit signal is much stronger (compared to that in the optical band), due to the extended atmosphere. The effective Lyman-$\alpha$ emission from the planet also shows a phase variation as the planet orbits around the star. We investigate how the transit and phase-change light curve depends on the distribution of neutral hydrogen in the atmosphere, as well as the velocity of the atmosphere. [Preview Abstract] |
Friday, October 17, 2014 10:51AM - 11:03AM |
B6.00003: An X-ray study of the massive star-forming cluster IRAS 20126$+$4104 Virginie Montes Massive star formation remains not well understood. The study of high-mass stars clusters is a key to explain massive star formation. Until recently it was believed that massive stars were only formed in dense molecular clouds leading to a substantial cluster. The study of 43 Galactic O-type stars by de Wit et al. (2005) showed that 4{\%} of high-mass stars are formed outside of a cluster. A way to understand the role of clustering in massive star formation is to study and characterize the cluster in which they remain, using X-ray observations and multiwavelenght data. X-ray is a good tracer to identify Young Stellar Objects that no longer have circumstellar disk to be detected in infrared or radio. The study allows us to determine number, age, mass, spectral type of stars, and contamination by associating X-ray observations with infrared, optical and radio data. Here, I present the Chandra X-ray study of the massive star-forming cluster IRAS 20126$+$4104. Discussion will include the work done on the X-ray data processing and model fitting, as well as the cluster properties combining infrared (2MASS), radio (EVLA) and optical (USNO) counterparts. Additionally, a cluster comparison done with M17 (Broos et al. 2007) will be presented. [Preview Abstract] |
Friday, October 17, 2014 11:03AM - 11:15AM |
B6.00004: Radio Emission Toward Regions of Massive Star Formation in the Large Magellanic Cloud Adam Johanson, Victor Migenes A survey for radio emission at 6 GHz and 9 GHz toward three regions of massive star formation in the Large Magellanic Cloud revealed eight ultracompact HII regions associated with known high-mass young stellar objects. Three of these are first-time detections. We find that they occupy a specific region of color-magnitude space, and suggest this criteria be used for future searches of ultracompact HII regions. An additional 30 compact sources were imaged, 19 of which are new detections. Many of these objects are active galactic nuclei candidates based on their radio spectral indices and mid-infrared colors. [Preview Abstract] |
Follow Us |
Engage
Become an APS Member |
My APS
Renew Membership |
Information for |
About APSThe American Physical Society (APS) is a non-profit membership organization working to advance the knowledge of physics. |
© 2024 American Physical Society
| All rights reserved | Terms of Use
| Contact Us
Headquarters
1 Physics Ellipse, College Park, MD 20740-3844
(301) 209-3200
Editorial Office
100 Motor Pkwy, Suite 110, Hauppauge, NY 11788
(631) 591-4000
Office of Public Affairs
529 14th St NW, Suite 1050, Washington, D.C. 20045-2001
(202) 662-8700