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GCN Circulars

GCN Circulars are rapid bulletins submitted by and distributed to the community. 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"

3615 results found.

  1. LIGO/Virgo S190728q Global MASTER-Net observations report
  2. LIGO/Virgo S190727h: No counterpart candidates in KAIT observations
  3. LIGO/Virgo S190727h: No counterpart candidates in the Swift/BAT Observations
  4. LIGO/Virgo S190727h: No counterpart candidates in Fermi-LAT observations
  5. LIGO/Virgo S190727h: possible counterpart candidate in SPI-ACS/INTEGRAL
  6. LIGO/Virgo S190727h: Upper limits from Fermi-GBM Observations
  7. LIGO/Virgo S190727h: No counterpart candidates in HAWC observations
  8. LIGO/Virgo S190727h : no neutrino counterpart candidate in ANTARES search
  9. LIGO/Virgo S190727h: No counterpart candidates in AGILE-MCAL observations
  10. LIGO/Virgo S190727h: No counterpart candidates in INTEGRAL SPI-ACS prompt observation
  11. LIGO/Virgo S190727h: Coverage and upper limits from MAXI/GSC observations
  12. LIGO/Virgo S190727h: Identification of a GW compact binary merger candidate
  13. LIGO/Virgo S190727h Global MASTER-Net observations report
  14. LIGO/Virgo S190727h: Upper limits from IceCube neutrino searches
  15. LIGO/Virgo S190718y: Classification of AT 2019lqm / Gaia19dcs as a Type Ia Supernova
  16. LIGO/Virgo S190718y: Classification of AT 2019lqn / Gaia19dct as a Type Ia Supernova
  17. LIGO/Virgo S190718y: Swift XRT observations, 45 X-ray sources
  18. LIGO/Virgo S190720a: Thacher Observatory follow-up observations
  19. LIGO/Virgo S190718y: Gaia Photometric Alerts transient candidates
  20. IPN triangulation of GRB 190720A
  21. LIGO/Virgo S190720a: Updated localization from LIGO and Virgo data
  22. LIGO/Virgo S190720a: No counterpart candidates in CNEOST observations
  23. LIGO/Virgo S190720a: No counterpart candidates in Fermi-LAT observations
  24. LIGO/Virgo S190720a: Upper limits from CALET observations
  25. LIGO/Virgo S190720a: No counterpart candidates in KAIT observations
  26. LIGO/Virgo S190720a: No counterpart candidates in the Swift/BAT Observations
  27. LIGO/Virgo S190720a: Upper limits from Fermi-GBM Observations
  28. LIGO/Virgo S190720a: Upper limits from AGILE-GRID observations
  29. LIGO/Virgo S190720a : no neutrino counterpart candidate in ANTARES search
  30. LIGO/Virgo S190720a: No counterpart candidates in INTEGRAL SPI-ACS and IBIS prompt observation
  31. LIGO/Virgo S190720a: Coverage and upper limits from MAXI/GSC observations
  32. LIGO/Virgo S190718y: No counterpart candidates in CNEOST
  33. LIGO/Virgo S190720a: AGILE-MCAL observations
  34. LIGO/Virgo S190720a: Identification of a GW compact binary merger candidate
  35. LIGO/Virgo S190720a Global MASTER-Net observations report
  36. LIGO/Virgo S190720a: No counterpart candidates in HAWC observations
  37. LIGO/Virgo S190720a: Upper limits from IceCube neutrino searches
  38. LIGO/Virgo S190718y: No counterpart candidates in KAIT observations
  39. LIGO/Virgo S190718y: ZTF pre-detection of MASTER candidate AT2019lly
  40. LIGO/Virgo S190718y: Analysis update
  41. MASTER OT detection inside LIGO/Virgo S190718y error box
  42. LIGO/Virgo S190718y: Upper limits from Insight-HXMT/HE observations
  43. LIGO/Virgo S190718y: No counterpart candidates in Fermi-LAT observations
  44. LIGO/Virgo S190718y: Coverage and upper limits from MAXI/GSC observations
  45. LIGO/Virgo S190718y: Upper limits from CALET observations
  46. LIGO/Virgo S190718y: No counterpart candidates in the Swift/BAT Observations
  47. LIGO/Virgo S190718y: Upper limits from Fermi-GBM Observations
  48. LIGO/Virgo S190630ag: Updated sky localization
  49. LIGO/Virgo S190718y: No counterpart candidates in INTEGRAL SPI-ACS prompt observation
  50. LIGO/Virgo S190718y : no neutrino counterpart candidate in ANTARES search
  51. LIGO/Virgo S190718y Global MASTER-Net observations report
  52. LIGO/Virgo S190718y: Identification of a GW compact binary merger candidate
  53. LIGO/Virgo S190718y: Upper limits from IceCube neutrino searches
  54. LIGO/Virgo S190706ai: Upper limits from Insight-HXMT/HE observations
  55. LIGO/Virgo S190706ai: Updated sky localization
  56. LIGO/Virgo S190707q: Updated sky localization
  57. LIGO/Virgo S190707q: MASTER OT seach result
  58. LIGO/Virgo S190707q: No counterpart candidates in the CNEOST
  59. LIGO/Virgo S190707q: No counterpart candidates in the Swift/BAT Observations
  60. IPN triangulation of GRB 190706D (short)
  61. IPN triangulation of GRB 190706C (long/very bright)
  62. LIGO/Virgo S190707q: Upper limits from CALET observations
  63. LIGO/Virgo S190707q: No counterpart candidates in Fermi-LAT observations
  64. LIGO/Virgo S190707q: No counterpart candidates in INTEGRAL SPI-ACS and IBIS prompt observations
  65. LIGO/Virgo S190706ai: No counterpart candidates in KAIT observations
  66. LIGO/Virgo S190706ai: No transient candidates from CALET observations
  67. LIGO/Virgo S190707q: Upper limits from Fermi-GBM Observations
  68. LIGO/Virgo S190706ai: No counterpart candidates in the Swift/BAT Observations
  69. LIGO/Virgo S190707q Global MASTER-Net observations report
  70. LIGO/Virgo S190706ai: No counterpart candidates in Fermi-LAT observations
  71. LIGO/Virgo S190701ah: No counterpart candidates in Fermi-LAT observations
  72. LIGO/Virgo S190707q: Upper limits from AGILE-GRID observations
  73. LIGO/Virgo S190707q: No counterpart candidates in AGILE-MCAL observations
  74. LIGO/Virgo S190707q: No counterpart candidates in HAWC observations
  75. LIGO/Virgo S190706ai: Upper limits from Fermi-GBM Observations
  76. LIGO/Virgo S190701ah: GRAWITA VST-ESO PARANAL observations
  77. LIGO/Virgo S190707q: Coverage and upper limits from MAXI/GSC observations
  78. LIGO/Virgo S190707q : No neutrino counterpart candidates in ANTARES search
  79. LIGO/Virgo S190707q: Identification of a GW compact binary merger candidate
  80. LIGO/Virgo S190707q: Upper limits from IceCube neutrino searches
  81. LIGO/Virgo S190706ai: No counterpart candidates in INTEGRAL SPI-ACS and IBIS prompt observations
  82. LIGO/Virgo S190706ai: No neutrino counterpart candidates in ANTARES search
  83. LIGO/Virgo S190706ai: Upper limits from AGILE-GRID observations
  84. LIGO/Virgo S190706ai: No counterpart candidates in HAWC observations
  85. LIGO/Virgo S190706ai: Coverage and upper limits from MAXI/GSC observations
  86. LIGO/Virgo S190706ai: No counterpart candidates in AGILE-MCAL observations
  87. LIGO/Virgo S190706ai Global MASTER-Net observations report
  88. LIGO/Virgo S190706ai: Identification of a GW compact binary merger candidate
  89. LIGO/Virgo S190706ai: Upper limits from IceCube neutrino searches
  90. LIGO/Virgo S190701ah: Updated sky localization
  91. LIGO/Virgo IceCube-190704A: No counterpart candidates in INTEGRAL SPI- ACS and IBIS prompt observation
  92. LIGO/Virgo S190630ag: Gaia Photometric Alerts transient candidate
  93. LIGO/Virgo S190630ag: no counterpart candidate in the SVOM/GWAC observations
  94. LIGO/Virgo S190701ah: KMTNet Observation
  95. LIGO/Virgo S190701ah: No transient candidates from CALET observations
  96. LIGO/Virgo S190701ah: Upper limits from Insight-HXMT/HE observations
  97. LIGO/Virgo S190701ah: No counterpart candidates in the Swift/BAT Observations
  98. IPN triangulation of GRB 190630A (short)
  99. LIGO/Virgo S190701ah: Upper limits from AGILE-GRID observations
  100. LIGO/Virgo S190630ag: Upper limits from Insight-HXMT/HE observations

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