Name | 069477 |
Title | Can accretion shocks of very-low-mass stars produce X-ray emission? |
URL | https://nxsa.esac.esa.int/nxsa-sl/servlet/data-action-aio?obsno=0694770101 |
DOI | https://doi.org/10.5270/esa-z6u5ofg |
Author | Dr Costanza Argiroffi |
Description | The accretion process in young stars produces intense X-rays. Very-low-mass stars (VLMS) cannot have post-shock hotter than 2MK, preventing any X-ray emission. Nonetheless 2 accreting VLMS showed X-rays from accretion shocks. To confirm or reject this finding we propose to observe 3 other accreting VLMS with XMM-EPIC (10ks for each target) to measure the plasma temperature, and hence distinguish between X-rays due to corona or to accretion. Accretion-driven X-rays in VLMS would indicate post-shocks hotter than 2MK, possible only if accretion velocity is higher than free fall velocity. Checking the hypothesis of accretion-driven X-rays in VLMS is fundamental to test whether another mechanism, other than gravity, accelerates accreting material. |
Publication | No observations found associated with the current proposal |
Instrument | EMOS1, EMOS2, EPN, OM, RGS1, RGS2 |
Temporal Coverage | 2012-10-13T18:33:50Z/2013-01-11T02:42:50Z |
Version | 17.56_20190403_1200 |
Mission Description | The European Space Agency's (ESA) X-ray Multi-Mirror Mission (XMM-Newton) was launched by an Ariane 504 on December 10th 1999. XMM-Newton is ESA's second cornerstone of the Horizon 2000 Science Programme. It carries 3 high throughput X-ray telescopes with an unprecedented effective area, and an optical monitor, the first flown on a X-ray observatory. The large collecting area and ability to make long uninterrupted exposures provide highly sensitive observations. Since Earth's atmosphere blocks out all X-rays, only a telescope in space can detect and study celestial X-ray sources. The XMM-Newton mission is helping scientists to solve a number of cosmic mysteries, ranging from the enigmatic black holes to the origins of the Universe itself. Observing time on XMM-Newton is being made available to the scientific community, applying for observational periods on a competitive basis. |
Creator Contact | https://www.cosmos.esa.int/web/xmm-newton/xmm-newton-helpdesk |
Date Published | 2014-01-29T00:00:00Z |
Publisher And Registrant | European Space Agency |
Credit Guidelines | European Space Agency, 2014-01-29T00:00:00Z, 069477, 17.56_20190403_1200. https://doi.org/10.5270/esa-z6u5ofg |