For a long time high-redshift BL Lac objects were deemed not to exist. Fermishowed us that there is r^ant population of BL Lacs with redshift beyond 1.0.Some of them belong to the high-synchrotron peaked (HSP) class and are among thehardest gamma-ray sources detected by Fermi showing emission up and beyond 100GeV. This makes them the most luminous BL Lacs ever detected and rates themamong the most powerful accelerators in the Universe. We plan to observe 3extreme BL Lacs simultaneously with XMM-Newton, GROND and Swift. This willprovide unprecedented coverage of the synchrotron peak from IR to hard X-rayallowing us: to understand the nature and the energetic of these objects, toanswer long-standing questions on the blazar sequence and to use them as probes of the EBL.
Instrument
EMOS1, EMOS2, EPN, OM, RGS1, RGS2
Temporal Coverage
2014-09-01T05:24:19Z/2015-01-05T01:12:00Z
Version
17.56_20190403_1200
Mission Description
The European Space Agencys (ESA) X-ray Multi-Mirror Mission (XMM-Newton) was launched by an Ariane 504 on December 10th 1999. XMM-Newton is ESAs 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 Earths 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.
European Space Agency, Dr Marco Ajello, 2016, 'BL Lac Objects at the highest redshifts', 17.56_20190403_1200, European Space Agency, https://doi.org/10.5270/esa-ud46kdn
