GCN Circulars
GCN Circulars are rapid astronomical bulletins submitted by and distributed to community members worldwide. They are used to share discoveries, observations, quantitative near-term predictions, requests for follow-up observations, or future observing plans related to high-energy, multi-messenger, and variable or transient astrophysical events. See the documentation for help with subscribing to or submitting Circulars.
To navigate to a specific circular, enter the associated Circular ID (e.g. 'gcn123', 'Circular 123', or '123').
286 results found.
- LIGO/Virgo S240422ed: No counterpart candidates in INTEGRAL SPI-ACS prompt observation
- IceCube-Cascade 240416A: Upper limits from a search for additional neutrino events in IceCube
- IceCube-240412A: Upper limits from a search for additional neutrino events in IceCube
- IceCube-240327A: Upper limits from a search for additional neutrino events in IceCube
- IceCube-240229A: Upper limits from a search for additional neutrino events in IceCube
- IceCube-240204A: Upper limits from a search for additional neutrino events in IceCube
- IceCube-240123A: Upper limits from a search for additional neutrino events in IceCube
- GRB 240106A: Glowbug gamma-ray detection
- IceCube-240105A: Upper limits from a search for additional neutrino events in IceCube
- IceCube-231211A: Upper limits from a search for additional neutrino events in IceCube
- Fermi GRB 231108A: Global MASTER-Net observations report
- LIGO/Virgo/KAGRA S231014r: Identification of a GW compact binary merger candidate
- LIGO/Virgo S230802aq: No counterpart candidates in INTEGRAL SPI-ACS prompt observation
- IceCube-230727A: Upper limits from a search for additional neutrino events in IceCube
- IceCube-230725A: Upper limits from a search for additional neutrino events in IceCube
- IceCube-230708A: Upper limits from a search for additional neutrino events in IceCube
- IceCube-230707B: Upper limits from a search for additional neutrino events in IceCube
- LIGO/Virgo/KAGRA S230527c: No counterpart candidates in INTEGRAL SPI-ACS prompt observation
- IceCube-Cascade 230610A: Upper limits from a search for additional neutrino events in IceCube
- LIGO/Virgo/KAGRA S230609u: Identification of a GW compact binary merger candidate
- LIGO/Virgo/KAGRA S230529ay: No counterpart candidates in INTEGRAL SPI-ACS prompt observation
- LIGO/Virgo/KAGRA S230518h: Upper limits from Glowbug gamma-ray observations
- LIGO/Virgo S230518h: No counterpart candidates in INTEGRAL SPI-ACS prompt observation
- IceCube-Cascade 230511A: Upper limits from a search for additional neutrino events in IceCube
- IceCube-Cascade 230430A: Upper limits from a search for additional neutrino events in IceCube
- IceCube-230416A: Upper limits from a search for additional neutrino events in IceCube
- IceCube-230405A: Upper limits from a search for additional neutrino events in IceCube
- INTEGRAL detection of a burst from SGR 1806-200
- GRB 230307A: soft X-ray detection with LEIA
- GRB 230307A: GECAM detection of an extremely bright burst
- IceCube-230220A: Upper limits from a search for additional neutrino events in IceCube
- IceCube-230201A: Upper limits from a search for additional neutrino events in IceCube
- IceCube-230122A: Upper limits from a search for additional neutrino events in IceCube
- Fermi-LAT gamma-ray observations of IceCube-230112A
- IceCube-221229A: Upper limits from a search for additional neutrino events in IceCube
- Fermi-LAT gamma-ray observations of IceCube-221223A
- IceCube-221216A: Upper limits from a search for additional neutrino events in IceCube
- IceCube-221124A: Upper limits from a search for additional neutrino events in IceCube
- IceCube-221104A: Upper limits from a search for additional neutrino events in IceCube
- Konus-Wind observation of the recent SGR 1935+2154 activity
- INTEGRAL detection of a burst from SGR J1935+2154
- IceCube-220928A: Upper limits from a search for additional neutrino events in IceCube
- IceCube-Cascade 220826A: Upper limits from a search for additional neutrino events in IceCube
- IceCube-220629A: Upper limits from a search for additional neutrino events in IceCube
- IceCube-220627A: Upper limits from a search for additional neutrino events in IceCube
- IceCube-Cascade 220625A: Upper limits from a search for additional neutrino events in IceCube
- GRB 220518A: Swift/UVOT Detection
- IceCube-220509A: Upper limits from a search for additional neutrino events in IceCube
- IceCube-220425A: Upper limits from a search for additional neutrino events in IceCube
- IceCube-220424A: Upper limits from a search for additional neutrino events in IceCube
- IceCube-220421A: Upper limits from a search for additional neutrino events in IceCube
- IceCube-220317A: Upper limits from a search for additional neutrino events in IceCube
- IceCube-220306A: Upper limits from a search for additional neutrino events in IceCube
- IceCube-220303A: Upper limits from a search for additional neutrino events in IceCube
- GRB 220228A: Fermi-LAT detection
- GRB 220101A: The first example of a Petanova
- IceCube-220205A: Upper limits from a search for additional neutrino events in IceCube
- IceCube-211216A: Upper limits from a search for additional neutrino events in IceCube
- IceCube-211216A: No counterpart candidates in INTEGRAL SPI-ACS and IBIS prompt observation
- IceCube-211208A: Upper limits from a search for additional neutrino events in IceCube
- IceCube-211208A: No counterpart candidates in INTEGRAL SPI-ACS and IBIS prompt observation
- IceCube-Cascade 211128A: Upper limits from a search for additional neutrino events in IceCube
- IceCube-211125A: No counterpart candidates in INTEGRAL SPI-ACS and IBIS prompt observation
- IceCube-211123A: Upper limits from a search for additional neutrino events in IceCube
- HAWC-211123A: No counterpart candidates in INTEGRAL SPI-ACS and IBIS prompt observation
- Konus-Wind observation of the recent SGR 1935+2154 activity
- IceCube-210730A: No counterpart candidates in INTEGRAL SPI-ACS and IBIS prompt observation
- IceCube-210717A: No counterpart candidates in INTEGRAL SPI-ACS and IBIS prompt observation
- INTEGRAL detection of a burst from SGR 1935+2154
- IceCube-210516A: No counterpart candidates in INTEGRAL SPI-ACS and IBIS prompt observation
- IceCube-210510A: No counterpart candidates in INTEGRAL SPI-ACS and IBIS prompt observation
- IceCube-210629A: No counterpart candidates in INTEGRAL SPI-ACS and IBIS prompt observation
- Fermi GRB 210510A: Global MASTER-Net observations report
- Fermi-LAT Gamma-ray Observations of IceCube-210503A and detection of a new gamma-ray source, Fermi J0931.9+3633
- GRB 210402A: MASTER prompt and follow up optical observation
- Fermi-LAT Gamma-ray Observations of IceCube-210210A
- IceCube-210210A: No counterpart candidates in INTEGRAL SPI-ACS and IBIS prompt observation
- Konus-Wind detection of two bright bursts from SGR 1935+2154
- NuEm-210111A: No counterpart candidates in INTEGRAL SPI-ACS and IBIS prompt observation
- IceCube-201222A: No counterpart candidates in INTEGRAL SPI-ACS and IBIS prompt observation
- IceCube-201221A: No counterpart candidates in INTEGRAL SPI-ACS and IBIS prompt observation
- IceCube-201209A: No counterpart candidates in INTEGRAL SPI-ACS and IBIS prompt observation
- IceCube-201130A: No counterpart candidates in INTEGRAL SPI-ACS and IBIS prompt observation
- IceCube-201120A: No counterpart candidates in INTEGRAL SPI-ACS and IBIS prompt observation
- IceCube-201115A: No counterpart candidates in INTEGRAL SPI-ACS and IBIS prompt observation
- IceCube-201114A: No counterpart candidates in INTEGRAL SPI-ACS and IBIS prompt observation
- VLASS identifies possible radio counterparts to IceCube-201115A, including a bright BL Lac candidate
- IceCube-201021A: No counterpart candidates in INTEGRAL SPI-ACS and IBIS prompt observation
- IceCube-201014A: No counterpart candidates in INTEGRAL SPI-ACS and IBIS prompt observation
- IceCube-201007A: No counterpart candidates in INTEGRAL SPI-ACS and IBIS prompt observation
- IceCube-200926B: No counterpart candidates in INTEGRAL SPI-ACS and IBIS prompt observation
- IceCube-200929A: No counterpart candidates in INTEGRAL SPI-ACS and IBIS prompt observation
- Fermi-LAT Gamma-ray Observations of IceCube-200926B
- IceCube-200921A: No counterpart candidates in INTEGRAL SPI-ACS and IBIS prompt observation
- IceCube-200916A: No counterpart candidates in INTEGRAL SPI-ACS and IBIS prompt observation
- Fermi-LAT Gamma-ray Observations of IceCube-200916A
- IceCube-200911A: No counterpart candidates in INTEGRAL SPI-ACS and IBIS prompt observation
- IceCube-200806A: No counterpart candidates in INTEGRAL SPI-ACS and IBIS prompt observation
- Fermi-LAT Gamma-ray Observations of IceCube-200806A
- IceCube-200615A: No counterpart candidates in INTEGRAL SPI-ACS prompt observation