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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"

45501 results found.

  1. GRB 241108A: Swift-XRT observations
  2. LIGO/Virgo/KAGRA S241109p: Identification of a GW compact binary merger candidate
  3. EP241107A: MASTER optical observations of xray transient
  4. EP241107a: KAIT optical observations
  5. GRB 241108A: Swift ToO observations
  6. GRB 241030A: TESS observations
  7. GRB 241108A: COLIBRÍ Upper Limits on the Optical Counterpart
  8. GRB 241108A : a likely weak long GRB detected by SVOM/ECLAIRs
  9. EP241107a: Kinder optical follow-up observations
  10. GRB 241025A: radio detection with the VLA
  11. GRB 241104A: CALET Gamma-Ray Burst Monitor detection
  12. EP241107a: AKO Optical Afterglow Follow-Up Observations
  13. EP241107a: GSP detects optical counterpart
  14. EP241107a: Gemini-South spectroscopic confirmation (z = 0.456)
  15. GRB 241107A: SVOM/GRM detection of a short burst
  16. GRB 241105A: EP-FXT follow-up observations
  17. GRB 241105A: SVOM/GRM observation
  18. EP241107a: OHP/T193 photometric and spectroscopic observations
  19. GRB 241105a: PRIME near-infrared upper limits
  20. EP241107a: FTW Optical and NIR observations of the optical counterpart
  21. GRB 241105A: ePESSTO+ NTT optical afterglow detection
  22. EP241107a: GIT optical observations
  23. EP241107a: Global MASTER-Net observations report
  24. EP241107a: SVOM/C-GFT optical observations
  25. EP241107a: AKO Optical Afterglow Detection
  26. GRB 241025A: LBT optical observations
  27. GRB241105A: Gemini-South Optical Afterglow Detection
  28. EP241107a: EP on-board trigger and autonomous follow-up observation
  29. GRB 241105A: VLT/FORS2 optical afterglow rapid fading
  30. GRB 241105A: Swift/UVOT Detection
  31. EP241101a: CrAO ZTSH optical observations
  32. GRB 241105A: Swift/BAT-GUANO refined analysis of short burst with extended emission
  33. GRB 241030A: optical afterglow detection from the INAF Asiago Observatory
  34. GRB 241105A: BOOTES-7 optical detection
  35. GRB 241030A: Mondy optical observations
  36. GRB 241105A: Fermi GBM Observation of a Short Burst with Extended Emission
  37. Konus-Wind detection of GRB 241105A (short with extended emission)
  38. LIGO/Virgo/KAGRA S241106ba: 1 counterpart neutrino candidate event from an IceCube neutrino search
  39. LIGO/Virgo/KAGRA S241102o: 1 counterpart neutrino candidate event from an IceCube neutrino search
  40. Konus-Wind detection of GRB 241021A
  41. GRB 241105A: SVOM/VT optical afterglow observations
  42. GRB 241105A: Swift-XRT afterglow detection
  43. GRB 241105A: VLT/FORS2 spectroscopic redshift z = 2.681
  44. GRB 241104A: Swift-XRT observations
  45. GRB 240511A: LCO upper limits
  46. GRB 241104A: Fermi GBM Observation
  47. GRB 241104A: The SVOM/VT candidate in GCN circular 38086 is not an astrophysical source
  48. GRB 241105A: Swift ToO observations
  49. GRB 241105A: Swift/BAT-GUANO arcminute localization of a short burst
  50. GRB 241104A: Swift ToO observations
  51. GRB 241104A: NOT optical non-detection
  52. GRB 241105A: GOTO tentative optical counterpart candidate
  53. Fermi GRB 241105A: Global MASTER-Net observations report
  54. GRB 241104A: SVOM/VT optical candidate
  55. GRB 241105A: Fermi GBM Final Real-time Localization
  56. GRB 241104A/EP241104a: Optical upper limits with Kinder observations
  57. GRB 241104A: COLIBRÍ Upper Limits on the Optical Counterpart
  58. GRB 241104A: SVOM/GRM observation
  59. EP241104a: EP detection of GRB 241104A X-ray emission
  60. GRB 241010A: host galaxy redshift z = 0.977
  61. EP241101a NUTTelA-TAO / BSTI Measurements 2024-11-02
  62. GRB 241104A : Detection and localization by SVOM/ECLAIRs
  63. GRB 240821A: further radio observations with the VLA
  64. Fermi GRB 241104A: Global MASTER-Net observations report
  65. GRB 241104A: Fermi GBM Final Real-time Localization
  66. GRB 241030A: GRBAlpha detection
  67. EP241101a: EP-FXT observations update
  68. EP241103a: GIT optical upper limit
  69. EP241021a: OHP/T193 further optical observations
  70. LIGO/Virgo/KAGRA S241104a: Retraction of GW compact binary merger candidate
  71. Fermi trigger No 752365806: Global MASTER-Net observations report
  72. LIGO/Virgo/KAGRA S241102br: OHP/T193 optical observations
  73. LIGO/Virgo/KAGRA S241102cy: Updated Sky localization
  74. EP241103a: GOTO optical upper limit
  75. LIGO/Virgo/KAGRA S241102br: Updated Sky localization
  76. EP241101a: Possible detection of an optical counterpart with FTW
  77. EP241103a: Swift XRT detection and improved X-ray position
  78. EP241021a: continued SOAR observations
  79. EP241101a: Optical upper limits with Kinder observations
  80. EP241101a: OHP/T193 optical observations
  81. EP241103a: Gemini optical limits
  82. EP241103a: EP observation update
  83. LIGO/Virgo/KAGRA S241102br: MASTER observations and OT detection
  84. LIGO/Virgo/KAGRA S241102br: EP-WXT X-ray follow-up and flux limits
  85. GRB 241030A: Swift-UVOT observations of the optical prompt flare
  86. EP241103a: GSP optical upper limit
  87. EP241103A: LCO optical observations
  88. EP241103a: Global MASTER-Net observations report
  89. EP241103a: an X-ray transient detected by Einstein Probe
  90. GRB 241030A: Rapid release of TESS data.
  91. EP241101a: Global MASTER-Net observations report
  92. GRB 241029A: GRBAlpha detection
  93. EP241101a: BOOTES-7 optical upper limit
  94. LIGO/Virgo/KAGRA S241101ee: Updated Sky localization
  95. S241102cy: Identification of a GW compact binary merger candidate
  96. LIGO/Virgo/KAGRA S241102br: NED Galaxies in the Localization Volume
  97. LIGO/Virgo/KAGRA S241102br: Identification of a GW compact binary merger candidate
  98. Kinder optical follow-up observations of EP241021a, EP241026b, and EP241030a/GRB241030A
  99. GRB241030A: OHP/T193 optical observations
  100. EP241030a: Futher EP-FXT observation of the X-ray Afterglow of GRB 241030A

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