Skip to main content
Updates to LVK & CHIME Notices, Schema v7.2.3! See news and announcements

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.

Search for Circulars by submitter, subject, or body text (e.g. 'Fermi GRB').
To navigate to a specific circular, enter the associated Circular ID (e.g. 'gcn123', 'Circular 123', or '123').
Advanced Search

To narrow the search results, use advanced search syntax. This allows for specifying which circular field to search (submitter, subject, and/or body). For additional information, refer to the advanced search documentation.

Advanced Search Examples (click to copy):

subject:"Swift"
body:"GRB"
submitter:"Judith Racusin"

350 results found.

  1. IceCube-191215A: No counterpart candidates in INTEGRAL SPI-ACS prompt observation
  2. LIGO/Virgo S191213g: No counterpart candidates in INTEGRAL SPI-ACS prompt observation
  3. LIGO/Virgo S191204r: No counterpart candidates in Fermi-LAT observations
  4. LIGO/Virgo S191205ah: No counterpart candidates in INTEGRAL SPI-ACS prompt observation
  5. IceCube-191204A: No counterpart candidates in INTEGRAL SPI-ACS prompt observation
  6. LIGO/Virgo S191204r: No counterpart candidates in INTEGRAL SPI-ACS prompt observation
  7. Fermi-LAT Gamma-ray Observations of IceCube-191119A
  8. IceCube-191119A - No counterpart candidates in INTEGRAL SPI-ACS prompt observation
  9. LIGO/Virgo S191110af: Potential pulsar counterparts
  10. Konus-Wind observation of the recent SGR 1935+2154 activity
  11. LIGO/Virgo S191110af: No counterpart candidates in INTEGRAL SPI-ACS, and IBIS prompt observation
  12. LIGO/Virgo S191110af: No counterpart candidates in INTEGRAL SPI-ACS, prompt observation
  13. LIGO/Virgo S191109d: No counterpart candidates in INTEGRAL SPI-ACS,prompt observation
  14. LIGO/Virgo S191105e: No counterpart candidates in INTEGRAL SPI-ACS and,IBIS prompt observation
  15. IceCube-191001A: No counterpart candidates in INTEGRAL SPI-ACS prompt observation
  16. LIGO/Virgo S190930t: No counterpart candidates in INTEGRAL SPI-ACS prompt observation
  17. LIGO/Virgo S190930s: No counterpart candidates in INTEGRAL SPI-ACS prompt observation
  18. Fermi-LAT Gamma-ray Observations of IceCube-190922B
  19. LIGO/Virgo S190924h: No counterpart candidates in INTEGRAL SPI-ACS and IBIS prompt observation
  20. LIGO/Virgo S190923y: No counterpart candidates in INTEGRAL SPI-ACS prompt observation
  21. IceCube-190922A: No counterpart candidates in INTEGRAL SPI-ACS prompt observation
  22. HAWC-190916A: No counterpart candidates in INTEGRAL SPI-ACS prompt observation
  23. LIGO/Virgo S190915ak: No counterpart candidates in INTEGRAL SPI-ACS prompt observation
  24. LIGO/Virgo S190910h: No counterpart candidates in INTEGRAL SPI-ACS prompt observation
  25. LIGO/Virgo S190910d: No counterpart candidates in INTEGRAL SPI-ACS prompt observation
  26. LIGO/Virgo S190901ap: No counterpart candidates in INTEGRAL SPI-ACS,prompt observation
  27. LIGO/Virgo S190828l: No counterpart candidates in INTEGRAL SPI-ACS prompt observation
  28. LIGO/Virgo S190828j: No counterpart candidates in INTEGRAL SPI-ACS prompt observation
  29. Fermi GBM-190816: Location-dependent upper limits from INTEGRAL/SPI-ACS prompt observation
  30. IceCube-190819A: No counterpart candidates in INTEGRAL SPI-ACS prompt observation
  31. HAWC-190806A: upper limits from INTEGRAL SPI-ACS and IBIS prompt observation
  32. IceCube 190730A: one weakly associated counterpart candidates in INTEGRAL SPI-ACS, and IBIS prompt observation
  33. Fermi-LAT Gamma-ray Observations of IceCube-190712A
  34. Fermi-LAT Gamma-ray Observations of IceCube-190504A
  35. LIGO/Virgo S190426c: Fermi-LAT search for a high-energy gamma-ray counterpart
  36. LIGO/Virgo S190425z: Las Cumbres Observatory Galaxy Targeted Counterpart Search
  37. INTEGRAL observations of the events in the GWTC-1 catalog
  38. GRB 181201A: a long GRB detected by INTEGRAL
  39. GRB 180809A: further Swift/XRT observations
  40. GRB 180701A/MAXI J2119-045: CALET Gamma-Ray Burst Monitor data search
  41. GRB 180728A: VLT/X-shooter redshift of a nearby energetic GRB
  42. GRB 180701A: MAXI/GSC detection
  43. LIGO/Virgo G298048: Chandra X-ray Update on GW170817
  44. LIGO/Virgo G298048: Discovery of X-ray emission from SSS17a in NGC4993
  45. LIGO/Virgo G298936: Astrosat CZTI upper limits
  46. LIGO/Virgo G298048: INTEGRAL pointed follow-up observations
  47. LIGO/Virgo G298048: Chandra X-ray observations
  48. GRB170730A detecetd by INTEGRAL. Refined analysis
  49. LIGO/Virgo G275697: DLT40 follow-up observation
  50. LIGO/Virgo G268556/GW170104: Lomonosov BDRG observations
  51. Swift-BAT refined analysis of the recent outburst from SGR 1617-5103 (a.k.a. 1E 161348-5055 and 2E 1613.5-5053)
  52. GRB 160401A: a long GRB detected by INTEGRAL
  53. LIGO/Virgo G184098: Fermi-GBM ground-based follow-up
  54. GRB 150912A: A long GRB detected by INTEGRAL
  55. SGR 1E 1841-045 (Swift trigger 649113): Terskol upper limit
  56. Fermi GBM triggers bn150715759 and bn150715817 are not due to GRBs
  57. Trigger 649113: Swift detection of SGR 1E 1841-045
  58. Swift trigger 642453 is not an astrophysical source
  59. GRB 140710B: a long GRB detected with INTEGRAL
  60. GRB 140705A / SGR 1935+2154: Probable association with supernova remnant G57.2+0.8
  61. Swift detection of a bright X-ray source in M31
  62. GRB 131108A: AGILE/GRID observation
  63. Observation of possible GRB/TDE 130925A by INTEGRAL/SPI-ACS: three activity episodes
  64. IPN Triangulation of SGR-like burst 130913 - probable association with SGR/AXP 1E1841-045
  65. GRB 130907A: INTEGRAL/SPI-ACS light curve
  66. GRB 130609B: Swift/UVOT Observations
  67. GRB 130513A: a long GRB detected by INTEGRAL
  68. Swift-BAT refined analysis of SGR 1E 1841-045 (Trigger=543763)
  69. Trigger 543763: SGR 1E 1841-045: Swift detection of a soft gamma repeater burst (aka Kes 73)
  70. GRB 121102A : a long GRB detected by INTEGRAL
  71. GRB 121027A: Swift-XRT refined Analysis
  72. Fermi/GBM detection of an SGR-like burst
  73. Swift-BAT refined analysis of 1E 1841-045 (Trigger=526660)
  74. Trigger 526660: Swift detection of 1 E 1841-045 (aka Kes 73)
  75. GRB 120624B: Swift-XRT observations
  76. GRB 120512A: A long GRB detected by INTEGRAL
  77. Fermi/GBM detection of a burst from the magnetar 1E 2259+5
  78. Swift J1822.3-1606: Transient Magnetar or Be X-ray Binary?
  79. SGR 1E 1841-045: early optical limit by "Pi of the Sky"
  80. SGR 1E 1841-045: Swift-BAT refined analysis
  81. SGR 1E 1841-045: Swift detection of a soft gamma repeater burst
  82. GRB 110625A: Fermi GBM and LAT observations
  83. SGR 1E 1841-045: Swift-BAT refined analysis
  84. SGR 1E 1841-045: Swift detection of a soft gamma repeater burst
  85. ICSP VLF observation of multiple SGR-like bursts from 1E 1841-045 on Feb. 9, 2011
  86. Fermi GBM detection of an SGR-like burst
  87. Swift-BAT refined analysis of outburst from 1E 1841-04.5
  88. Fermi GBM detection of a burst from 1E 1841-045
  89. SGR-like outburst from the magnetar 1E 1841-04.5
  90. GRB 110112B: A short GRB detected by INTEGRAL
  91. An SGR-like burst from the magnetar 1E 1841-04.5 in Kes 73
  92. GRB 100316D: Pre-burst emission measured by BAT
  93. GRB 090709A: Quasiperiodic variations in the BAT light curve
  94. XRF 090702: Swift-XRT refined analysis
  95. A bright burst from AXP 1E 1547.0-5408/SGR J1550-5418
  96. SGR J1550-5418
  97. IBAS Alert N. 5442 is not a GRB
  98. Suzaku ToO Observation of AXP 1E 1547.0-5408
  99. Konus-Wind observation of AXP/SGR 1E1547.0-5408 bursting activity
  100. GRB 090111: Swift UVOT Upper Limits

Advanced

Download all Circulars as a .tar.gz archive (updated once a day):
Looking for U.S. government information and services? Visit USA.gov