A dataset provided by the European Space Agency

Name 010507
Title The nature of high Lx/Lopt sources
URL

https://nxsa.esac.esa.int/nxsa-sl/servlet/data-action-aio?obsno=0105070101
https://nxsa.esac.esa.int/nxsa-sl/servlet/data-action-aio?obsno=0105070201

DOI https://doi.org/10.5270/esa-01narjg
Author European Space Agency
Description GT- While the majority of X-ray sources from serendipitous surveys have been
identified, a significant fraction (10-20%) have no optical counterpart down to
magnitudes, Rvirgul20. These objects have eluded identification to date; possible
candidates are diskless quasars, isolated neutron stars, optically-poor
clusters, or even a new category of high Lx/Lopt sources not yet discovered. We
propose observations of two bright X-ray sources from WGACAT with high optical
to X-ray flux ratios (>80, this limit is higher than that for any known class
of object). The XMM images will give accurate X-ray positions for these sources
which, together with the OM data, provide firm evidence for their
identification or for follow-up work, if necessary.
Publication No observations found associated with the current proposal
Instrument EMOS1, EMOS2, EPN, OM, RGS1, RGS2
Temporal Coverage 2002-07-02T18:38:15Z/2002-07-05T11:21:11Z
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 2003-09-04T00:00:00Z
Publisher And Registrant European Space Agency
Credit Guidelines European Space Agency, 2003, The Nature Of High Lx/Lopt Sources, 17.56_20190403_1200, European Space Agency, https://doi.org/10.5270/esa-01narjg