Abstract for Proposal 086086
Revealing Accreting Millisecond X-ray Pulsars with XMM-Newton
We propose a ToO observation of Galactic X-ray transients aimed at
discovering AMXPs. XMM-Newton represents an ideal observatory capable
of fulfilling such goal, which will help increasing the knowledge of
the evolutionary paths of NS, and possibly lead to the discoveries of
extremely quickly rotating objects. We propose a 30 ks observation
of newly discovered X-ray transients. Criteria set to maximise the
probability of discovering new sources of this class, based on the
X-ray flux, the spectral shape, and the absence of an alternative
identification, will be used to trigger the proposed observations among
newly discovered transients. We emphasise that the proposal has been
allocated XMM-Newton observing time in B priority during AO-18 but
never triggered.
Details on Observing Strategy and Trigger Criteria
The proposed ToO would be triggered by: 1) a flux larger than 7 and
10 mCrab in 2-10 and 20-40 keV energy bands, (equivalent to 2E-10 and
8E-11 erg cm-2s-1), to observe sources bright enough to detect signals
with amplitudes >5%; 2) an energy spectrum described by a power-law with
index ranging from 1.5 to 2.5; 3) no alternative identification driven by,
e.g. a bright O/B optical counterpart, long period ( > 1 s) pulsations,
or very short ( < 1 s) bursts typical of soft gamma-ray repeaters.