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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"

45842 results found.

  1. GRB 241025C: VZLUSAT-2 detection
  2. GRB 241025A: VZLUSAT-2 detection
  3. GRB 241018A: cubesat Avion detection
  4. Fermi trigger No 752990530: Global MASTER-Net observations report
  5. GRB 241111A: Fermi GBM Final Real-time Localization
  6. GRB 241030B: TESS detection of optical counterpart
  7. LIGO/Virgo/KAGRA S241110br: Updated Sky localization
  8. LIGO/Virgo/KAGRA S241110bk: 1 counterpart neutrino candidate event from an IceCube neutrino search
  9. LIGO/Virgo/KAGRA S241110br: Identification of a GW compact binary merger candidate
  10. LIGO/Virgo/KAGRA S241109bn: Upper limits from EP-WXT observations
  11. Fermi trigger No 752878030: Global MASTER-Net observations report
  12. Integral GRB241109.89: Global MASTER-Net observations report
  13. LIGO/Virgo/KAGRA S241109bn: Coverage and upper limits from MAXI/GSC observations
  14. EP241109a: KAIT photometry and 3 m Shane spectroscopy from Lick observatory
  15. LIGO/Virgo/KAGRA S241109bn: Updated Sky localization and EM Bright Classification
  16. INTEGRAL detection of a burst from 1E 1841-045
  17. EP241107a: AbAO optical upper limit
  18. LIGO/Virgo/KAGRA S241109bn: Upper limits from Fermi-GBM Observations
  19. GRB 241108A: Further COLIBRÍ Upper Limits on the Optical Counterpart
  20. LIGO/Virgo/KAGRA S241109p: Updated Sky localization and Source Classification
  21. LIGO/Virgo/KAGRA S241109bn: Global MASTER-Net observations report
  22. LIGO/Virgo/KAGRA S241109bn: Identification of a GW compact binary merger candidate
  23. EP241109a: confirmation of a stellar flare by BOOTES-7
  24. EP241109a: EP on-board trigger and autonomous follow-up observation
  25. GRB 241108A: Swift-XRT observations
  26. LIGO/Virgo/KAGRA S241109p: Identification of a GW compact binary merger candidate
  27. EP241107A: MASTER optical observations of xray transient
  28. EP241107a: KAIT optical observations
  29. GRB 241108A: Swift ToO observations
  30. GRB 241030A: TESS observations
  31. GRB 241108A: COLIBRÍ Upper Limits on the Optical Counterpart
  32. GRB 241108A : a likely weak long GRB detected by SVOM/ECLAIRs
  33. EP241107a: Kinder optical follow-up observations
  34. GRB 241025A: radio detection with the VLA
  35. GRB 241104A: CALET Gamma-Ray Burst Monitor detection
  36. EP241107a: AKO Optical Afterglow Follow-Up Observations
  37. EP241107a: GSP detects optical counterpart
  38. EP241107a: Gemini-South spectroscopic confirmation (z = 0.456)
  39. GRB 241107A: SVOM/GRM detection of a short burst
  40. GRB 241105A: EP-FXT follow-up observations
  41. GRB 241105A: SVOM/GRM observation
  42. EP241107a: OHP/T193 photometric and spectroscopic observations
  43. GRB 241105a: PRIME near-infrared upper limits
  44. EP241107a: FTW Optical and NIR observations of the optical counterpart
  45. GRB 241105A: ePESSTO+ NTT optical afterglow detection
  46. EP241107a: GIT optical observations
  47. EP241107a: Global MASTER-Net observations report
  48. EP241107a: SVOM/C-GFT optical observations
  49. EP241107a: AKO Optical Afterglow Detection
  50. GRB 241025A: LBT optical observations
  51. GRB241105A: Gemini-South Optical Afterglow Detection
  52. EP241107a: EP on-board trigger and autonomous follow-up observation
  53. GRB 241105A: VLT/FORS2 optical afterglow rapid fading
  54. GRB 241105A: Swift/UVOT Detection
  55. EP241101a: CrAO ZTSH optical observations
  56. GRB 241105A: Swift/BAT-GUANO refined analysis of short burst with extended emission
  57. GRB 241030A: optical afterglow detection from the INAF Asiago Observatory
  58. GRB 241105A: BOOTES-7 optical detection
  59. GRB 241030A: Mondy optical observations
  60. GRB 241105A: Fermi GBM Observation of a Short Burst with Extended Emission
  61. Konus-Wind detection of GRB 241105A (short with extended emission)
  62. LIGO/Virgo/KAGRA S241106ba: 1 counterpart neutrino candidate event from an IceCube neutrino search
  63. LIGO/Virgo/KAGRA S241102o: 1 counterpart neutrino candidate event from an IceCube neutrino search
  64. Konus-Wind detection of GRB 241021A
  65. GRB 241105A: SVOM/VT optical afterglow observations
  66. GRB 241105A: Swift-XRT afterglow detection
  67. GRB 241105A: VLT/FORS2 spectroscopic redshift z = 2.681
  68. GRB 241104A: Swift-XRT observations
  69. GRB 240511A: LCO upper limits
  70. GRB 241104A: Fermi GBM Observation
  71. GRB 241104A: The SVOM/VT candidate in GCN circular 38086 is not an astrophysical source
  72. GRB 241105A: Swift ToO observations
  73. GRB 241105A: Swift/BAT-GUANO arcminute localization of a short burst
  74. GRB 241104A: Swift ToO observations
  75. GRB 241104A: NOT optical non-detection
  76. GRB 241105A: GOTO tentative optical counterpart candidate
  77. Fermi GRB 241105A: Global MASTER-Net observations report
  78. GRB 241104A: SVOM/VT optical candidate
  79. GRB 241105A: Fermi GBM Final Real-time Localization
  80. GRB 241104A/EP241104a: Optical upper limits with Kinder observations
  81. GRB 241104A: COLIBRÍ Upper Limits on the Optical Counterpart
  82. GRB 241104A: SVOM/GRM observation
  83. EP241104a: EP detection of GRB 241104A X-ray emission
  84. GRB 241010A: host galaxy redshift z = 0.977
  85. EP241101a NUTTelA-TAO / BSTI Measurements 2024-11-02
  86. GRB 241104A : Detection and localization by SVOM/ECLAIRs
  87. GRB 240821A: further radio observations with the VLA
  88. Fermi GRB 241104A: Global MASTER-Net observations report
  89. GRB 241104A: Fermi GBM Final Real-time Localization
  90. GRB 241030A: GRBAlpha detection
  91. EP241101a: EP-FXT observations update
  92. EP241103a: GIT optical upper limit
  93. EP241021a: OHP/T193 further optical observations
  94. LIGO/Virgo/KAGRA S241104a: Retraction of GW compact binary merger candidate
  95. Fermi trigger No 752365806: Global MASTER-Net observations report
  96. LIGO/Virgo/KAGRA S241102br: OHP/T193 optical observations
  97. LIGO/Virgo/KAGRA S241102cy: Updated Sky localization
  98. EP241103a: GOTO optical upper limit
  99. LIGO/Virgo/KAGRA S241102br: Updated Sky localization
  100. EP241101a: Possible detection of an optical counterpart with FTW

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