P.A. Evans (U. Leicester), J.A. Kennea (PSU), S.D. Barthelmy
(NASA/GSFC), A.P. Beardmore (U. Leicester), A.A. Breeveld (UCL-MSSL),
D.N. Burrows (PSU), S. Campana (INAF-OAB), S.B. Cenko (NASA/GSFC), G.
Cusumano (INAF-IASF PA), A. D'Ai (INAF-IASFPA), P. D'Avanzo (INAF-OAB),
V.D'Elia(ASDC), P. Giommi (ASI), C. Gronwall (PSU), H.A. Krimm
(CRESST/GSFC/USRA), N.P.M. Kuin (UCL-MSSL), A.Y. Lien (GSFC/UMBC), F.E.
Marshall (NASA/GSFC), A. Melandri (INAF-OAB), B. Mingo (U. Leicester),
J.A. Nousek (PSU), S.R. Oates (U. Warwick), P.T. O'Brien (U.
Leicester), J.P. Osborne (U. Leicester), C. Pagani (U. Leicester), K.L.
Page (U.Leicester), D.M. Palmer (LANL), M. Perri (ASDC), J.L. Racusin
(NASA/GSFC), B. Sbarufatti (INAF-OAB/PSU), M.H. Siegel (PSU), G.
Tagliaferri (INAF-OAB), E. Troja (NASA/GSFC/UMCP) on behalf of the Swift
Francesco Verrecchia (ASDC) and Marco Tavani (INAF / University of Rome
Tor Vergata) on behalf of the AGILE team report:
Swift-XRT has performed pointed observations of two sources within the
error region of the AGILE-GRID transient AGL J1914+1043 (Tavani et al.
LVC Circ. 20754): the IR transient reported by Yoshida et al (LVC Circ.
20784) and the Galactic microquasar GRS 1915+105, observing each field
No X-ray source is detected at the location of the IR transient, with a
3-sigma upper limit of 9.7e-3 ct/sec. Assuming a power-law spectrum with
Gamma=1.7 and NH=1.43e22 cm^-2 (the Galactic column along this line of
sight; Willingale et al. 2013) this corresponds to an observed X-ray
flux of 7.1e-13 erg cm^-2 s^-1.
GRS 1915+105 is a known X-ray emitter and is clearly detected in the XRT
observations, with a mean count-rate of 87.8 (+1.63, -2.05) ct/sec,
which is ~20% lower than seen in Swift observations from 2016 November.
This circular is an official produce of the Swift and AGILE teams.