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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"

32720 results found.

  1. GRB 241112B: SVOM/GRM observation
  2. GRB 241112B: SVOM/VT afterglow detection
  3. Fermi Gamma-ray Burst Monitor trigger 752995908/241111230 (GRB 241111A) is not a GRB
  4. GRB 241107A: Swift/BAT candidate arcminute localization of a short burst
  5. GRB 241112B: Mephisto optical upper limits
  6. GRB 241112B: GOTO optical upper limits
  7. GRB 241112B: Swift ToO observations
  8. GRB 241107A: INTEGRAL IBIS localization
  9. EP241107a: EP-FXT follow-up observations
  10. LIGO/Virgo/KAGRA S241109bn: ATLAS observations and discovery of the potential counterpart AT2024aawt
  11. GRB 241105A: VLT/FORS2 refined spectroscopic redshift z = 2.681
  12. LIGO/Virgo/KAGRA S241111bn: Identification of a GW compact binary merger candidate
  13. IPN triangulation of GRB 241107A (short/hard)
  14. GRB 241107A: INTEGRAL/IBIS/PICsIT detection of a short burst
  15. GRB 241025C: VZLUSAT-2 detection
  16. GRB 241025A: VZLUSAT-2 detection
  17. GRB 241018A: cubesat Avion detection
  18. GRB 241030B: TESS detection of optical counterpart
  19. LIGO/Virgo/KAGRA S241110br: Updated Sky localization
  20. LIGO/Virgo/KAGRA S241110br: Identification of a GW compact binary merger candidate
  21. LIGO/Virgo/KAGRA S241109bn: Upper limits from EP-WXT observations
  22. LIGO/Virgo/KAGRA S241109bn: Coverage and upper limits from MAXI/GSC observations
  23. EP241109a: KAIT photometry and 3 m Shane spectroscopy from Lick observatory
  24. LIGO/Virgo/KAGRA S241109bn: Updated Sky localization and EM Bright Classification
  25. EP241107a: AbAO optical upper limit
  26. LIGO/Virgo/KAGRA S241109bn: Upper limits from Fermi-GBM Observations
  27. GRB 241108A: Further COLIBRÍ Upper Limits on the Optical Counterpart
  28. LIGO/Virgo/KAGRA S241109p: Updated Sky localization and Source Classification
  29. LIGO/Virgo/KAGRA S241109bn: Identification of a GW compact binary merger candidate
  30. EP241109a: confirmation of a stellar flare by BOOTES-7
  31. LIGO/Virgo/KAGRA S241109p: Identification of a GW compact binary merger candidate
  32. EP241107A: MASTER optical observations of xray transient
  33. EP241107a: KAIT optical observations
  34. GRB 241108A: Swift ToO observations
  35. GRB 241030A: TESS observations
  36. GRB 241108A: COLIBRÍ Upper Limits on the Optical Counterpart
  37. EP241107a: Kinder optical follow-up observations
  38. GRB 241025A: radio detection with the VLA
  39. GRB 241104A: CALET Gamma-Ray Burst Monitor detection
  40. EP241107a: AKO Optical Afterglow Follow-Up Observations
  41. EP241107a: GSP detects optical counterpart
  42. EP241107a: Gemini-South spectroscopic confirmation (z = 0.456)
  43. GRB 241105A: EP-FXT follow-up observations
  44. GRB 241105A: SVOM/GRM observation
  45. EP241107a: OHP/T193 photometric and spectroscopic observations
  46. GRB 241105a: PRIME near-infrared upper limits
  47. EP241107a: FTW Optical and NIR observations of the optical counterpart
  48. GRB 241105A: ePESSTO+ NTT optical afterglow detection
  49. EP241107a: GIT optical observations
  50. EP241107a: Global MASTER-Net observations report
  51. EP241107a: SVOM/C-GFT optical observations
  52. EP241107a: AKO Optical Afterglow Detection
  53. GRB 241025A: LBT optical observations
  54. GRB241105A: Gemini-South Optical Afterglow Detection
  55. GRB 241105A: VLT/FORS2 optical afterglow rapid fading
  56. GRB 241105A: Swift/UVOT Detection
  57. EP241101a: CrAO ZTSH optical observations
  58. GRB 241105A: Swift/BAT-GUANO refined analysis of short burst with extended emission
  59. GRB 241030A: optical afterglow detection from the INAF Asiago Observatory
  60. GRB 241030A: Mondy optical observations
  61. GRB 241105A: Fermi GBM Observation of a Short Burst with Extended Emission
  62. Konus-Wind detection of GRB 241105A (short with extended emission)
  63. Konus-Wind detection of GRB 241021A
  64. GRB 241105A: SVOM/VT optical afterglow observations
  65. GRB 241105A: Swift-XRT afterglow detection
  66. GRB 241105A: VLT/FORS2 spectroscopic redshift z = 2.681
  67. GRB 241104A: Swift-XRT observations
  68. GRB 240511A: LCO upper limits
  69. GRB 241104A: Fermi GBM Observation
  70. GRB 241104A: The SVOM/VT candidate in GCN circular 38086 is not an astrophysical source
  71. GRB 241105A: Swift ToO observations
  72. GRB 241105A: Swift/BAT-GUANO arcminute localization of a short burst
  73. GRB 241104A: Swift ToO observations
  74. GRB 241104A: NOT optical non-detection
  75. GRB 241105A: GOTO tentative optical counterpart candidate
  76. Fermi GRB 241105A: Global MASTER-Net observations report
  77. GRB 241104A: SVOM/VT optical candidate
  78. GRB 241104A/EP241104a: Optical upper limits with Kinder observations
  79. GRB 241104A: COLIBRÍ Upper Limits on the Optical Counterpart
  80. GRB 241104A: SVOM/GRM observation
  81. EP241104a: EP detection of GRB 241104A X-ray emission
  82. GRB 241010A: host galaxy redshift z = 0.977
  83. EP241101a NUTTelA-TAO / BSTI Measurements 2024-11-02
  84. GRB 241104A : Detection and localization by SVOM/ECLAIRs
  85. GRB 240821A: further radio observations with the VLA
  86. Fermi GRB 241104A: Global MASTER-Net observations report
  87. GRB 241030A: GRBAlpha detection
  88. EP241101a: EP-FXT observations update
  89. EP241103a: GIT optical upper limit
  90. EP241021a: OHP/T193 further optical observations
  91. LIGO/Virgo/KAGRA S241102br: OHP/T193 optical observations
  92. LIGO/Virgo/KAGRA S241102cy: Updated Sky localization
  93. EP241103a: GOTO optical upper limit
  94. LIGO/Virgo/KAGRA S241102br: Updated Sky localization
  95. EP241101a: Possible detection of an optical counterpart with FTW
  96. EP241103a: Swift XRT detection and improved X-ray position
  97. EP241021a: continued SOAR observations
  98. EP241101a: Optical upper limits with Kinder observations
  99. EP241101a: OHP/T193 optical observations
  100. EP241103a: Gemini optical limits

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