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We detected a gamma-ray flare from the TeV HBL blazar 1ES 1011+496 (z=0.212), triggering on FERMI-LAT data at E > 10 GeV with TS ~50, from 2015-03-12 to 2015-03-16, following the prescription of Pacciani et al.

We detected a gamma-ray flare from the FSRQ PKS 1441+25 (z=0.939), triggering on FERMI-LAT data at E > 10 GeV with TS ~44, from 2015-03-21 to 2015-04-15, following the prescription of Pacciani et al.

We detected a gamma-ray flare from the low-synchrotron-peaked BL Lac (z=0.135) S3 1227+25, triggering on FERMI-LAT data at E > 10 GeV with TS ~35, from 2015-05-06 to 2015-05-15, following the prescription of Pacciani et al. ...

We detected a gamma-ray flare from the FSRQ PKS 2032+107 (z=0.601), triggering on FERMI-LAT data at E > 10 GeV with TS ~46, from 2015-05-23 to 2015-06-02, following the prescription of Pacciani et al.

We asked a Swift ToO campaign on the FSRQ PKS 1502+106 (z=1.83853), triggered by prolonged High Energy activity detected with FERMI-LAT. The HE trigger detected activity at E > 10 GeV with TS ~153, from 2015-06-17 to 2015-07-10, following the prescription of Pacciani et al.

We report the discovery of a likely supernova (SN) at approximately 1 arcminute from the center of the galaxy cluster MACSJ0949.8+1708 (a.k.a. RXC J0949.8+1707, ZwCl 0947.2+1723).

We asked a Swift ToO campaign on the FSRQ PKS 2320-035 (z=1.411), triggered by prolonged High Energy activity detected with FERMI-LAT. The trigger method detected activity at E > 20GeV/(1+z) with TS ~44 and emission up to 54 GeV from 2015-09-03 to 2015-11-16, following the prescription of Pacciani et al. 2014, ApJ, 790, 45. The flux integrated on the whole period is (32.1+-1.6)E^-8 ph cm^-2 s^-1 (E > 0.1 GeV), and the gamma-ray photon index 2.20+-0.06.

We asked a Swift ToO campaign on the FSRQ PKS 1313-333 (z=1.21), triggered by prolonged High Energy activity detected with FERMI-LAT. The trigger method detected activity at E > 20GeV/(1+z) with TS ~79 from 2015-12-10 to 2015-12-30, following the prescription of Pacciani et al. 2014, ApJ, 790, 45. FERMI-LAT detected Two Gamma-ray photons of about 50 GeV within the last week.

The Large Area Telescope (LAT), one of the two instruments on the Fermi Gamma-ray Space Telescope, has observed unusually high activity above 10 GeV from a source positionally consistent with the flat spectrum radio quasar S4 1030+61 (z=1.40).

Accretion disks are one of the key ingredients of the star formation process. They redistribute angular momentum and, in the case of high-mass stars (M > 8Msun), disks would relieve the radiation pressure on the accreting material, in particular in the equatorial direction, by beaming the radiation through the poles of the system and this would allow the accretion to proceed onto the central protostar (e.g., Tan et al. 2014 for a review on massive star formation). In fact, in recent years, all high-mass star-forming theories appear to converge to a disk-mediated accretion scenario (e.g., Krumholz et al. 2007; Kuiper et al. 2011; Bonnell & Bate 2006; Keto 2007) but do the observations of high-mass young stellar objects (YSOs) confirm the theory predictions? Or in other words, do true accretion disks around massive stars really exist?

We report that the optical brightness of the flaring blazar BL Lacertae (RA: 22 02 43.29 Dec: +42 16 39.98 J2000.0) reached levels that are unprecedented for this source to the best of our knowledge, with observed magnitudes below R=11.5.

The XRT began observing the field of GRB 160712A at 20:47:52.7 UT, 3256.7 seconds after the BAT trigger. The position determined from promptly downlinked data differs significantly from the on-board position, suggesting that the XRT may have centroided on a cosmic ray; the initial XRT position notice should be treated with caution. Using promptly downlinked data we find an uncatalogued X-ray source with an enhanced position: RA, Dec 304.1600, -26.9582 which is equivalent to: RA(J2000) = 20h 16m 38.40s Dec(J2000) = -26d 57' 29.4" with an uncertainty of 2.1 arcseconds (radius, 90% containment). This location is 89 arcseconds from the BAT onboard position, within the BAT error circle. This position may be improved as more data are received; the latest position is available at http://www.swift.ac.uk/sper. A power-law fit to a spectrum formed from promptly downlinked event data gives a column density in excess of the Galactic value (8.30 x 10^20 cm^-2, Willingale et al. 2013), with an excess column of 2.7 (+2.97/-2.55) x 10^21 cm^-2 (90% confidence).

No abstract

GRB 190117A: AGILE/MCAL detection of a burst

Rubrica "spazio alla scuola"

Classification of the transients LSQ15bbb and LSQ15bbj from the LSQ observations. They are candidates in the G184098 error box.

We realised that the text of GCN 26390 was submitted while still incomplete. The correct text is the following: We report the results of the observation of the field of the gravitational wave event S191204r (GCN 26334) obtained with the VLT Survey Telescope (VST) equipped with Omegacam (described in GCN 26334, Proposal ID ESO 0104.D-0049). Images were analised using our image difference pipelines (Brocato et al. 2018 MNRAS, 474,1). As reference images we used DECAM archive images retrieced from https://datalab.noao.edu/sia/des_dr1 . The final vetting was done via visual inspection. We detected the following three interesting candidates: Name | RA | Dec | MJD | Mag VSTJ044435.43-332755.7 | 04:44:35.432 | -33:27:55.69 | 58222.081 | 21.5 +/- 0.1 VSTJ051111.58-373132.0 | 05:11:11.576 | -37:31:32.04 | 58822.079 | 20.6 +/- 0.1 VSTJ051052.17-335413.9 | 05:10:52.168 | -33:54:13.95 | 58823.140 | 22.2 +/- 0.2 The transients were detected at multiple epochs. Here we report epoch and magnitude for the brightest detection. All the transients appear projected near a galaxy. In particular VSTJ051111.58-373132.0 is located 7.4 arcsec from the nucleus of GLADE131392 which distance is 178Mpc (GLADE catalog). The small distance appears to exclude that this transient is related to the GW event. For the other two galaxies the distance is unknown. In the next days, a fourth observation epoch with the VST is scheduled to check for the transient luminosity evolution. We apologise for any confusion.

We report the results of the observation of the field of the gravitational wave event S191204r (GCN circular #26334) obtained with the VLT Survey Telescope (VST) equipped with Omegacam (described in GCN 26334, Proposal ID ESO 0104.D-0049). Images were analised using our image difference pipelines (Brocato et al. 2018 MNRAS, 474,1). As reference images we used DECAM archive images retrieved from https://datalab.noao.edu/sia/des_dr1. The final vetting was done via visual inspection. We detected the following three interesting candidates: Name | RA | Dec | MJD | Mag VSTJ044435.43-332755.7 | 04:44:35.432 | -33:27:55.69 | 58222.081 | 21.5 +/- 0.1 VSTJ051111.58-373132.0 | 05:11:11.576 | -37:31:32.04 | 58822.079 | 20.6 +/- 0.1 VSTJ051052.17-335413.9 | 05:10:52.168 | -33:54:13.95 | 58823.140 | 22.2 +/- 0.2 The transients were detected at multiple epochs. Here we report epoch and magnitude for the brightest detection. All the transients appear projected near a galaxy. In particular GWd_S191205r_12093 is located 7.4 arcsec from the nucleus of GLADE131392 which distance is 178Mpc (GLADE catalog). The small distance appears to exclude that this transient is related to the GW event. -- Too short? See why http://www.emailcharter.org/ <<<<<<<<<<<<<<<<<<<<>>>>>>>>>>>>>>>>>>>>> Aniello Grado, PhD Ricercatore Astronomo INAF- Osservatorio Astronomico di Capodimonte Via Moiariello 16 80131 Napoli ITALIA Tel: 0039 0815575547 Fax: 0039 0815575433 <<<<<<<<<<<<<<<<<<<<>>>>>>>>>>>>>>>>>>>>>

We obtained NIR observations of the faint transient AT2019wxt (PS19hgw; McBrien et al., GCN Circ. 26485), possibly associated with the gravitational wave event S191213g (LVC, GCN Circ. 26402), with the 3.58m TNG telescope equipped with NICS in imaging mode. A series of images were obtained with the J filter on 2019-12-18 from 19:16:04 to 19:59:02 UT (i.e. about 5.6 days after the GW event). The transient is clearly detected with a magnitude J(AB) = 19.6 +/- 0.1 (obtained from preliminary psf photometry calibrated against the 2MASS catalogue and subtracting the host galaxy contribution). [GCN OPS NOTE(19dec19): Per author's request, the Circular reference in the first line was changed from 26845 to 26485.]