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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').

276 results found.

  1. Fermi-LAT Gamma-ray Observations of IceCube-190523A
  2. Fermi-LAT Gamma-ray Observations of IceCube-200512A
  3. IceCube-200512A: No counterpart candidates in INTEGRAL SPI-ACS prompt observation
  4. Konus-Wind observation of SGR 1935+2154 activity on 2020 May 10
  5. IceCube-200425A: No counterpart candidates in INTEGRAL SPI-ACS prompt observation
  6. IceCube-200421A: No counterpart candidates in INTEGRAL SPI-ACS and IBIS prompt observation
  7. Fermi-LAT Gamma-ray Observations of IceCube-200410A
  8. IceCube-200410A: Possible associated excess in INTEGRAL SPI-ACS prompt observation
  9. LIGO/Virgo S200316bj: No counterpart candidates in INTEGRAL SPI-ACS, and IBIS prompt observation
  10. LIGO/Virgo S200311bg: No counterpart candidates in INTEGRAL SPI-ACS,prompt observation
  11. LIGO/Virgo S200302c: No counterpart candidates in INTEGRAL SPI-ACS and IBIS prompt observation
  12. Fermi-LAT Gamma-ray Observations of IceCube-200227A
  13. IceCube-200227A: No counterpart candidates in INTEGRAL SPI-ACS and IBIS prompt observation
  14. LIGO/Virgo S200225q: No counterpart candidates in INTEGRAL SPI-ACS and IBIS prompt observation
  15. LIGO/Virgo S200224ca: No counterpart candidates in INTEGRAL SPI-ACS prompt observation
  16. LIGO/Virgo S200219ac: No counterpart candidates in INTEGRAL SPI-ACS and IBIS prompt observation
  17. LIGO/Virgo S200213t: No counterpart candidates in INTEGRAL SPI-ACS prompt observation
  18. LIGO/Virgo S200208q: No counterpart candidates in INTEGRAL SPI-ACS prompt observation
  19. LIGO/Virgo S200129m: No counterpart candidates in INTEGRAL SPI-ACS prompt observation
  20. LIGO/Virgo S200128d: No counterpart candidates in INTEGRAL SPI-ACS prompt observation
  21. IceCube-200120A: no counterpart candidates in INTEGRAL SPI-ACS and,IBIS prompt observation
  22. IceCube-200117A: no counterpart candidates in INTEGRAL SPI-ACS and,IBIS prompt observation
  23. LIGO/Virgo S200114f: No counterpart candidates in INTEGRAL SPI-ACS and IBIS prompt observation
  24. LIGO/Virgo S200112r: upper limits from AGILE/GRID observations
  25. Fermi-LAT ANTARES coincidence: No counterpart candidates in INTEGRAL SPI-ACS and IBIS prompt observation
  26. Fermi-LAT Gamma-ray Observations of IceCube-200107A
  27. IceCube-200107A: No counterpart candidates in INTEGRAL SPI-ACS prompt observation
  28. LIGO/Virgo S200105ae: No counterpart candidates in INTEGRAL SPI-ACS prompt observation
  29. Fermi-LAT Gamma-ray Observations of IceCube-191231A
  30. IceCube-191231A: No counterpart candidates in INTEGRAL SPI-ACS and IBIS prompt observation
  31. Fermi-LAT Gamma-ray Observations of IceCube-191215A
  32. LIGO/Virgo S191215w: No counterpart candidates in INTEGRAL SPI-ACS prompt observation
  33. LIGO/Virgo S191215w: Identification of a GW compact binary merger candidate
  34. IceCube-191215A: No counterpart candidates in INTEGRAL SPI-ACS prompt observation
  35. LIGO/Virgo S191213g: No counterpart candidates in INTEGRAL SPI-ACS prompt observation
  36. LIGO/Virgo S191204r: No counterpart candidates in Fermi-LAT observations
  37. LIGO/Virgo S191205ah: No counterpart candidates in INTEGRAL SPI-ACS prompt observation
  38. IceCube-191204A: No counterpart candidates in INTEGRAL SPI-ACS prompt observation
  39. LIGO/Virgo S191204r: No counterpart candidates in INTEGRAL SPI-ACS prompt observation
  40. Fermi-LAT Gamma-ray Observations of IceCube-191119A
  41. IceCube-191119A - No counterpart candidates in INTEGRAL SPI-ACS prompt observation
  42. LIGO/Virgo S191110af: Potential pulsar counterparts
  43. Konus-Wind observation of the recent SGR 1935+2154 activity
  44. LIGO/Virgo S191110af: No counterpart candidates in INTEGRAL SPI-ACS, and IBIS prompt observation
  45. LIGO/Virgo S191110af: No counterpart candidates in INTEGRAL SPI-ACS, prompt observation
  46. LIGO/Virgo S191109d: No counterpart candidates in INTEGRAL SPI-ACS,prompt observation
  47. LIGO/Virgo S191105e: No counterpart candidates in INTEGRAL SPI-ACS and,IBIS prompt observation
  48. IceCube-191001A: No counterpart candidates in INTEGRAL SPI-ACS prompt observation
  49. LIGO/Virgo S190930t: No counterpart candidates in INTEGRAL SPI-ACS prompt observation
  50. LIGO/Virgo S190930s: No counterpart candidates in INTEGRAL SPI-ACS prompt observation
  51. Fermi-LAT Gamma-ray Observations of IceCube-190922B
  52. LIGO/Virgo S190924h: No counterpart candidates in INTEGRAL SPI-ACS and IBIS prompt observation
  53. LIGO/Virgo S190923y: No counterpart candidates in INTEGRAL SPI-ACS prompt observation
  54. IceCube-190922A: No counterpart candidates in INTEGRAL SPI-ACS prompt observation
  55. HAWC-190916A: No counterpart candidates in INTEGRAL SPI-ACS prompt observation
  56. LIGO/Virgo S190915ak: No counterpart candidates in INTEGRAL SPI-ACS prompt observation
  57. LIGO/Virgo S190910h: No counterpart candidates in INTEGRAL SPI-ACS prompt observation
  58. LIGO/Virgo S190910d: No counterpart candidates in INTEGRAL SPI-ACS prompt observation
  59. LIGO/Virgo S190901ap: No counterpart candidates in INTEGRAL SPI-ACS,prompt observation
  60. LIGO/Virgo S190828l: No counterpart candidates in INTEGRAL SPI-ACS prompt observation
  61. LIGO/Virgo S190828j: No counterpart candidates in INTEGRAL SPI-ACS prompt observation
  62. Fermi GBM-190816: Location-dependent upper limits from INTEGRAL/SPI-ACS prompt observation
  63. IceCube-190819A: No counterpart candidates in INTEGRAL SPI-ACS prompt observation
  64. HAWC-190806A: upper limits from INTEGRAL SPI-ACS and IBIS prompt observation
  65. IceCube 190730A: one weakly associated counterpart candidates in INTEGRAL SPI-ACS, and IBIS prompt observation
  66. Fermi-LAT Gamma-ray Observations of IceCube-190712A
  67. Fermi-LAT Gamma-ray Observations of IceCube-190504A
  68. LIGO/Virgo S190426c: Fermi-LAT search for a high-energy gamma-ray counterpart
  69. INTEGRAL observations of the events in the GWTC-1 catalog
  70. GRB 181201A: a long GRB detected by INTEGRAL
  71. GRB 180809A: further Swift/XRT observations
  72. GRB 180728A: VLT/X-shooter redshift of a nearby energetic GRB
  73. LIGO/Virgo G298048: Chandra X-ray Update on GW170817
  74. LIGO/Virgo G298048: Discovery of X-ray emission from SSS17a in NGC4993
  75. LIGO/Virgo G298936: Astrosat CZTI upper limits
  76. LIGO/Virgo G298048: INTEGRAL pointed follow-up observations
  77. LIGO/Virgo G298048: Chandra X-ray observations
  78. GRB170730A detecetd by INTEGRAL. Refined analysis
  79. LIGO/Virgo G268556/GW170104: Lomonosov BDRG observations
  80. Swift-BAT refined analysis of the recent outburst from SGR 1617-5103 (a.k.a. 1E 161348-5055 and 2E 1613.5-5053)
  81. GRB 160401A: a long GRB detected by INTEGRAL
  82. LIGO/Virgo G184098: Fermi-GBM ground-based follow-up
  83. GRB 150912A: A long GRB detected by INTEGRAL
  84. SGR 1E 1841-045 (Swift trigger 649113): Terskol upper limit
  85. Fermi GBM triggers bn150715759 and bn150715817 are not due to GRBs
  86. Trigger 649113: Swift detection of SGR 1E 1841-045
  87. Swift trigger 642453 is not an astrophysical source
  88. GRB 140710B: a long GRB detected with INTEGRAL
  89. GRB 140705A / SGR 1935+2154: Probable association with supernova remnant G57.2+0.8
  90. Swift detection of a bright X-ray source in M31
  91. GRB 131108A: AGILE/GRID observation
  92. Observation of possible GRB/TDE 130925A by INTEGRAL/SPI-ACS: three activity episodes
  93. GRB 130907A: INTEGRAL/SPI-ACS light curve
  94. GRB 130513A: a long GRB detected by INTEGRAL
  95. Swift-BAT refined analysis of SGR 1E 1841-045 (Trigger=543763)
  96. Trigger 543763: SGR 1E 1841-045: Swift detection of a soft gamma repeater burst (aka Kes 73)
  97. GRB 121102A : a long GRB detected by INTEGRAL
  98. GRB 121027A: Swift-XRT refined Analysis
  99. Swift-BAT refined analysis of 1E 1841-045 (Trigger=526660)
  100. Trigger 526660: Swift detection of 1 E 1841-045 (aka Kes 73)

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