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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"

20538 results found.

  1. GRB 241228B: Swift/BAT-GUANO localization skymap of a burst
  2. GRB241228B: GROWTH-India Telescope optical observations
  3. GRB 241226A: Swift/BAT-GUANO localization skymap of a burst
  4. GRB 241228A: GROWTH-India telescope optical upper limit
  5. GRB 241228B: TRT optical counterpart confirmation
  6. GRB 241228A: Swift/UVOT Upper Limits
  7. GRB 241228A: Enhanced Swift-XRT position
  8. GRB 241228A: Swift detection of a burst
  9. IceCube-241224A: Upper limits from a search for additional neutrino events in IceCube
  10. EP241223a: Mondy AZT-33IK optical observations
  11. GRB 241029A: LCO optical observation
  12. GRB 241223A: Swift-XRT observations
  13. LIGO/Virgo/KAGRA S241225v: Identification of a GW compact binary merger candidate
  14. GRB 241029A: AbAO AS-32 optical observations
  15. LIGO/Virgo/KAGRA S241225c: Identification of a GW compact binary merger candidate
  16. EP241223a
  17. EP241223a: EP-WXT detection of a fast X-ray transient
  18. GRB241113A: 7DT Optical upper limits
  19. GRB 241105A: JWST photometric observations of the host galaxy
  20. Fermi GRB 241221A: Global MASTER-Net observations report
  21. EP241217a: Liverpool Telescope optical upper limit
  22. EP241021a: VLA radio detection
  23. GRB 241218A: Mondy AZT-33IK optical upper limit
  24. EP241217a : Leavitt Observatory optical upper limit
  25. EP241217a: 1.6m Mephisto multi-band optical observations
  26. GRB 241217a/EP241217B: 1.6m Mephisto optical upper limits
  27. GRB 241218A: Swift/UVOT Upper Limits
  28. EP241217a: optical upper limit with the Liverpool Telescope
  29. Konus-Wind detection of GRB 241204A (short/hard)
  30. GRB 241218A: NOT optical upper limits
  31. GRB 241217A / EP241217B: GRANDMA/T1MPicduMidi optical upperlimits
  32. EP 241217a: NIR detection with P200/WIRC
  33. EP 241217a: Possible J-band detection with WINTER
  34. EP241217a: refined EP-WXT analysis and EP-FXT follow-up observations
  35. GRB 241217A / EP241217b: Nanshan/HMT optical upper limit
  36. GRB 241217A / EP241217b: NOT optical upper limits
  37. GRB 241218A: REM optical upper limit
  38. GRB 241217A/EP241217b: REM optical/NIR upper limits
  39. EP241217a: REM optical/NIR upper limits
  40. GRB 241217a: Liverpool Telescope optical follow-up
  41. EP241217a: Liverpool Telescope optical follow-up
  42. GRB 241218A: Swift-XRT refined Analysis
  43. EP241217a: NOT optical observations
  44. EP241217a: GROWTH-India Telescope optical observations
  45. GRB 241218A: NUTTelA-TAO / BSTI Optical Limits
  46. EP241119a: 7DT Optical upper limits
  47. EP241217a: Xinglong optical follow-up observations
  48. EP241217b/GRB 241217A: EP detection of the prompt X-ray emssion
  49. GRB 241218A: LCOGT Optical Upper Limit
  50. GRB 241218A: Enhanced Swift-XRT position
  51. GRB 241217A: GMG Optical Upper Limit
  52. GRB 241218A: Swift detection of a burst
  53. GRB 241217A : SVOM/VT optical afterglow detection
  54. GRB 241217A: Swift-XRT afterglow detection
  55. GRB 241217A: LCO optical upper limit
  56. GRB 241217A: GRANDMA/TAROT optical upperlimits
  57. EP241217a: Swift-XRT Detection
  58. GRB 241217A : SVOM/ECLAIRs,GRM,MXT detection of a long burst with a bright X-ray afterglow candidate
  59. EP241217a: Kinder optical follow-up observations
  60. EP241217A: LCO optical observations
  61. EP241217a: Gemini-North detection of the likely optical counterpart
  62. EP241217a: EP detection of an X-ray transient
  63. The EP-WXT trigger 01709129023 is likely a flaring star
  64. EP241107a: VLA Radio Observation
  65. GRB 241214A: Swift/BAT-GUANO localization skymap of a burst
  66. GRB 241215A: Mondy AZT-33IK optical observations
  67. GRB 241212A: Swift-XRT observations
  68. GRB 241215A: Nanshan/HMT optical upper limit
  69. GRB 241215A: Montarrenti Observatory optical upper limit
  70. GRB 241215A: GROWTH-India telescope optical upper limit
  71. The EP-WXT trigger 01709128921 is likely a flaring star
  72. GRB 241213A: Swift/UVOT Upper Limits
  73. EP241208a: NOT optical upper limits
  74. GRB 241213A: LCOGT Optical Upper Limits
  75. EP 241208A : Detection of a long soft transient by SVOM/ECLAIRs
  76. EP241213a: EP detection of An X-ray Transient
  77. GRB 241213A: REM optical/NIR upper limits
  78. GRB 241213A: Enhanced Swift-XRT position
  79. GRB241212A: OHP/T193 optical observations
  80. GRB 241213A: SAO RAS optical upper limit
  81. GRB 241213A: Swift detection of a burst
  82. GRB 241212A : SVOM/C-GFT optical upper limit at early phase
  83. GRB 241209B: GRANDMA/TRT upper limit
  84. GRB 241207A: TSHAO Zeiss-1000 optical observations
  85. GRB 241212A: SVOM detection of a bright long burst
  86. GRB 241209B: Swift/BAT-GUANO localization skymap of a burst
  87. GRB 241209D: REM optical/NIR upper limits
  88. GRB 241209B: Swift-XRT afterglow detection
  89. GRB 241209C: Fermi GBM Observation
  90. LIGO/Virgo/KAGRA S241210fu: Identification of a GW compact binary merger candidate
  91. EP241208a: Optical upper limit with Kinder observations
  92. LIGO/Virgo/KAGRA S241210cw: Identification of a GW compact binary merger candidate
  93. LIGO/Virgo/KAGRA S241210d: Identification of a GW compact binary merger candidate
  94. GRB 241209D: Fermi GBM Observation
  95. GRB 241209A: VLT/HAWK-I near-IR counterpart candidate
  96. GRB 241209D: COLIBRÍ detection of the afterglow
  97. GRB 241209A: COLIBRÍ Optical Upper Limit
  98. GRB 241209C: Swift/BAT-GUANO localization skymap of a burst
  99. GRB 241209A: GRANDMA/TAROT upper limit
  100. GRB 241209A: REM optical/NIR observations

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