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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"

32759 results found.

  1. EP240802a: Time coincidence with GRB 240802A and optical upper limits with Kinder observations
  2. EP240801a: further SAO RAS optical observations
  3. EP240801a: optical observations at CrAO and AbAO
  4. EP240801a: GRANDMA and Kilonova-Catcher optical observations
  5. EP240801a: Leavitt Observatory optical observations
  6. EP240801a: GTC spectroscopy and absorption redshift
  7. EP240801a: SAO RAS optical observations
  8. GRB 240801B: AstroSat CZTI Updated classification - likely a solar flare
  9. EP240801a: JinShan optical observations
  10. GRB 240727C: SVOM/GRM observation
  11. EP240801a: NOT optical observations
  12. EP240801a: follow-up observation with LCOGT
  13. Fermi GBM trigger 744179961 / 240801194 can not be confirmed as a GRB
  14. GRB 240730A: Swift-BAT refined analysis
  15. EP240801a: GSP follow-up observations of the candidate counterpart
  16. EP240801a: Kinder follow-up observations of the candidate counterpart
  17. EP240708a: Kinder follow-up observations of the candidate counterpart (duplicate submission of GCN 37002)
  18. EP240801a: KAIT optical counterpart observations
  19. EP240801a: GMG observation
  20. EP240801a: TRT optical counterpart detection
  21. Fermi GRB 240801A: Global MASTER-Net observations report
  22. GRB 240731A: Fermi GBM Final Localization
  23. GRB 240730A: Osservatorio Astronomico Nastro Verde upper limit
  24. Fermi GRB 240730B: Global MASTER-Net observations report
  25. Swift GRB 240730A: Global MASTER-Net observations report
  26. GRB 240715A: Swift-XRT afterglow detection
  27. GRB 240730A: KAIT Optical Upper Limit
  28. GRB 240727C: GRBAlpha detection
  29. GRB 240730A: Swift/UVOT Upper Limits
  30. GRB 240727A: Swift-BAT refined analysis
  31. LIGO/Virgo/KAGRA S240615dg: GRAWITA wide-field optical observations
  32. GRB 240727A: observations of optical counterpart.
  33. GRB 240727B: Swift-XRT observations
  34. Fermi GRB 240727A: Global MASTER-Net observations report
  35. GRB 240727A: Swift/UVOT detection
  36. GRB 240727A: Osservatorio Astronomico Nastro Verde upper limit
  37. GRB 240727A: NOT optical observation
  38. GRB 240727A: JinShan optical upper limits
  39. GRB 240727A Bassano Bresciano Observatory upper limit
  40. GRB 240727D: Correction to the GRB name in GCN 36958
  41. GRB 240720B: GRBAlpha detection
  42. GRB 240718A: GRBAlpha detection
  43. GRB 240627A: GRBAlpha detection
  44. Fermi GRB 240726A: Global MASTER-Net observations report
  45. GRB 240727B: Fermi GBM Observation
  46. GRB240529A: VIRT optical transient detection
  47. GRB 240727B: Swift ToO observations
  48. GRB 240727B: Swift/BAT-GUANO arcminute localization of a long burst
  49. GRB 240726A: SVOM/GRM observation
  50. GRB240727A: Skynet Optical Afterglow Observations
  51. GRB 240727A: TRT optical afterglow detection
  52. GRB 240727A: KAIT Optical Afterglow Candidate
  53. GRB 240726A: AstroSat CZTI detection of a short burst
  54. IceCube-240725A: Upper limits from a search for additional neutrino events in IceCube
  55. Fermi-LAT gamma-ray observations of IceCube-240725A
  56. IceCube-240721A: Two candidates from the Zwicky Transient Facility
  57. GRB 240720A: Swift-BAT refined analysis
  58. IceCube-240721A: Upper limits from a search for additional neutrino events in IceCube
  59. Fermi-LAT gamma-ray observations of IceCube-240721A
  60. Fermi Gamma-ray Burst Monitor trigger 743243582/240721356 (GRB 240721A) is not a GRB
  61. GRB 240720B: SVOM/GRM observation
  62. Fermi GRB 240720A: Global MASTER-Net observations report
  63. GRB 240720A: AstroSat CZTI detection
  64. GRB 240720A: Fermi GBM observation
  65. Konus-Wind detection of GRB 240718A
  66. GRB 240713A: SVOM/GRM observation
  67. Fermi GRB 240718A: Global MASTER-Net observations report
  68. GRB 240718A: Fermi GBM Observation
  69. IceCube-Cascade 240714A: TRT optical observations on the EP/FXT positions
  70. GRB 240718A: Fermi-LAT Detection
  71. GRB 240718A: SVOM/GRM observation
  72. GRB 240712A: Swift-BAT refined analysis
  73. GRB 240716A: GECAM-B detection of a long burst
  74. GRB 240715A: Swift/UVOT observations of the XRT sources.
  75. GRB240713A: Swift/UVOT Upper LImits
  76. EP240708a: X-ray follow-up observations with Swift/XRT
  77. GRB 240715A: GECAM-C detection of a short burst
  78. Konus-Wind detection of GRB 240715A
  79. LIGO/Virgo/KAGRA S240716b: Updated Sky localization
  80. GRB 240713A: Swift-XRT observations
  81. GRB 240715A: TRT optical upper limit on one Swift/XRT candidate
  82. SVOM/GRM In-Flight Trigger of GRB 240715A
  83. GRB 240713A: LAST optical upper limit
  84. LIGO/Virgo/KAGRA S240716b: Identification of a GW compact binary merger candidate
  85. GRB 240715A: Swift ToO observations
  86. Fermi GRB 240715A: Global MASTER-Net observations report
  87. GRB 240713A: optical upper limits from the INAF Asiago Observatory
  88. GRB 240715A: Fermi GBM Observation
  89. GRB 240712A ATCA radio observations
  90. GRB240715A: GRANDMA Optical Upper Limits
  91. IPN triangulation of GRB 240715A (short)
  92. GRB 240712A: Swift/UVOT Upper Limits
  93. EP-WXT flaring star and the optical flaring activity during its decay phase
  94. JinShan confirmation of the EP-WXT source triggered on July 14th due to a flaring star
  95. GRB 240713A: Tiled Swift observations
  96. GRB 240713A: J-band upper limit from WINTER
  97. GRB 240713A: NOT optical upper limits on three EP/FXT candidates
  98. GRB 240713A: JinShan optical upper limits
  99. GRB 240713A: OHP/T120 optical upper limit
  100. GRB240713A: X-ray follow-up observation with EP-FXT (duplicate submission of GCN 36859)

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