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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"

32767 results found.

  1. EP240802a: correction of EP-WXT trigger time in GCN 37019
  2. Fermi GRB 240804A: Global MASTER-Net observations report
  3. EP240802a: Montarrenti Observatory optical upper limit
  4. IPN triangulation of GRB 240802A / EP 240802a
  5. EP240801a: Osservatorio Astronomico Nastro Verde upper limit
  6. EP240802A: Bassano Bresciano Observatory upper limit
  7. GRB 240802A: SVOM/GRM observation
  8. EP240802a: Time coincidence with GRB 240802A and optical upper limits with Kinder observations
  9. EP240801a: further SAO RAS optical observations
  10. EP240801a: optical observations at CrAO and AbAO
  11. EP240801a: GRANDMA and Kilonova-Catcher optical observations
  12. EP240801a: Leavitt Observatory optical observations
  13. EP240801a: GTC spectroscopy and absorption redshift
  14. EP240801a: SAO RAS optical observations
  15. GRB 240801B: AstroSat CZTI Updated classification - likely a solar flare
  16. EP240801a: JinShan optical observations
  17. GRB 240727C: SVOM/GRM observation
  18. EP240801a: NOT optical observations
  19. EP240801a: follow-up observation with LCOGT
  20. Fermi GBM trigger 744179961 / 240801194 can not be confirmed as a GRB
  21. GRB 240730A: Swift-BAT refined analysis
  22. EP240801a: GSP follow-up observations of the candidate counterpart
  23. EP240801a: Kinder follow-up observations of the candidate counterpart
  24. EP240708a: Kinder follow-up observations of the candidate counterpart (duplicate submission of GCN 37002)
  25. EP240801a: KAIT optical counterpart observations
  26. EP240801a: GMG observation
  27. EP240801a: TRT optical counterpart detection
  28. Fermi GRB 240801A: Global MASTER-Net observations report
  29. GRB 240731A: Fermi GBM Final Localization
  30. GRB 240730A: Osservatorio Astronomico Nastro Verde upper limit
  31. Fermi GRB 240730B: Global MASTER-Net observations report
  32. Swift GRB 240730A: Global MASTER-Net observations report
  33. GRB 240715A: Swift-XRT afterglow detection
  34. GRB 240730A: KAIT Optical Upper Limit
  35. GRB 240727C: GRBAlpha detection
  36. GRB 240730A: Swift/UVOT Upper Limits
  37. GRB 240727A: Swift-BAT refined analysis
  38. LIGO/Virgo/KAGRA S240615dg: GRAWITA wide-field optical observations
  39. GRB 240727A: observations of optical counterpart.
  40. GRB 240727B: Swift-XRT observations
  41. Fermi GRB 240727A: Global MASTER-Net observations report
  42. GRB 240727A: Swift/UVOT detection
  43. GRB 240727A: Osservatorio Astronomico Nastro Verde upper limit
  44. GRB 240727A: NOT optical observation
  45. GRB 240727A: JinShan optical upper limits
  46. GRB 240727A Bassano Bresciano Observatory upper limit
  47. GRB 240727D: Correction to the GRB name in GCN 36958
  48. GRB 240720B: GRBAlpha detection
  49. GRB 240718A: GRBAlpha detection
  50. GRB 240627A: GRBAlpha detection
  51. Fermi GRB 240726A: Global MASTER-Net observations report
  52. GRB 240727B: Fermi GBM Observation
  53. GRB240529A: VIRT optical transient detection
  54. GRB 240727B: Swift ToO observations
  55. GRB 240727B: Swift/BAT-GUANO arcminute localization of a long burst
  56. GRB 240726A: SVOM/GRM observation
  57. GRB240727A: Skynet Optical Afterglow Observations
  58. GRB 240727A: TRT optical afterglow detection
  59. GRB 240727A: KAIT Optical Afterglow Candidate
  60. GRB 240726A: AstroSat CZTI detection of a short burst
  61. IceCube-240725A: Upper limits from a search for additional neutrino events in IceCube
  62. Fermi-LAT gamma-ray observations of IceCube-240725A
  63. IceCube-240721A: Two candidates from the Zwicky Transient Facility
  64. GRB 240720A: Swift-BAT refined analysis
  65. IceCube-240721A: Upper limits from a search for additional neutrino events in IceCube
  66. Fermi-LAT gamma-ray observations of IceCube-240721A
  67. Fermi Gamma-ray Burst Monitor trigger 743243582/240721356 (GRB 240721A) is not a GRB
  68. GRB 240720B: SVOM/GRM observation
  69. Fermi GRB 240720A: Global MASTER-Net observations report
  70. GRB 240720A: AstroSat CZTI detection
  71. GRB 240720A: Fermi GBM observation
  72. Konus-Wind detection of GRB 240718A
  73. GRB 240713A: SVOM/GRM observation
  74. Fermi GRB 240718A: Global MASTER-Net observations report
  75. GRB 240718A: Fermi GBM Observation
  76. IceCube-Cascade 240714A: TRT optical observations on the EP/FXT positions
  77. GRB 240718A: Fermi-LAT Detection
  78. GRB 240718A: SVOM/GRM observation
  79. GRB 240712A: Swift-BAT refined analysis
  80. GRB 240716A: GECAM-B detection of a long burst
  81. GRB 240715A: Swift/UVOT observations of the XRT sources.
  82. GRB240713A: Swift/UVOT Upper LImits
  83. EP240708a: X-ray follow-up observations with Swift/XRT
  84. GRB 240715A: GECAM-C detection of a short burst
  85. Konus-Wind detection of GRB 240715A
  86. LIGO/Virgo/KAGRA S240716b: Updated Sky localization
  87. GRB 240713A: Swift-XRT observations
  88. GRB 240715A: TRT optical upper limit on one Swift/XRT candidate
  89. SVOM/GRM In-Flight Trigger of GRB 240715A
  90. GRB 240713A: LAST optical upper limit
  91. LIGO/Virgo/KAGRA S240716b: Identification of a GW compact binary merger candidate
  92. GRB 240715A: Swift ToO observations
  93. Fermi GRB 240715A: Global MASTER-Net observations report
  94. GRB 240713A: optical upper limits from the INAF Asiago Observatory
  95. GRB 240715A: Fermi GBM Observation
  96. GRB 240712A ATCA radio observations
  97. GRB240715A: GRANDMA Optical Upper Limits
  98. IPN triangulation of GRB 240715A (short)
  99. GRB 240712A: Swift/UVOT Upper Limits
  100. EP-WXT flaring star and the optical flaring activity during its decay phase

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