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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"

21945 results found.

  1. GRB 241025A: radio detection with the VLA
  2. EP241107a: AKO Optical Afterglow Follow-Up Observations
  3. EP241107a: GSP detects optical counterpart
  4. GRB 241105A: SVOM/GRM observation
  5. EP241107a: OHP/T193 photometric and spectroscopic observations
  6. GRB 241105a: PRIME near-infrared upper limits
  7. GRB 241105A: ePESSTO+ NTT optical afterglow detection
  8. EP241107a: GIT optical observations
  9. EP241107a: SVOM/C-GFT optical observations
  10. EP241107a: AKO Optical Afterglow Detection
  11. GRB 241025A: LBT optical observations
  12. EP241107a: EP on-board trigger and autonomous follow-up observation
  13. GRB 241105A: VLT/FORS2 optical afterglow rapid fading
  14. GRB 241105A: Swift/UVOT Detection
  15. Konus-Wind detection of GRB 241105A (short with extended emission)
  16. GRB 241105A: Swift-XRT afterglow detection
  17. GRB 241104A: Swift-XRT observations
  18. GRB 240511A: LCO upper limits
  19. GRB 241105A: GOTO tentative optical counterpart candidate
  20. GRB 241104A: SVOM/VT optical candidate
  21. GRB 241105A: Fermi GBM Final Real-time Localization
  22. GRB 241104A/EP241104a: Optical upper limits with Kinder observations
  23. GRB 241104A: COLIBRÍ Upper Limits on the Optical Counterpart
  24. EP241104a: EP detection of GRB 241104A X-ray emission
  25. GRB 241010A: host galaxy redshift z = 0.977
  26. EP241101a NUTTelA-TAO / BSTI Measurements 2024-11-02
  27. GRB 240821A: further radio observations with the VLA
  28. GRB 241030A: GRBAlpha detection
  29. EP241103a: GIT optical upper limit
  30. EP241021a: OHP/T193 further optical observations
  31. LIGO/Virgo/KAGRA S241102br: OHP/T193 optical observations
  32. EP241103a: Swift XRT detection and improved X-ray position
  33. EP241021a: continued SOAR observations
  34. EP241101a: Optical upper limits with Kinder observations
  35. EP241101a: OHP/T193 optical observations
  36. LIGO/Virgo/KAGRA S241102br: EP-WXT X-ray follow-up and flux limits
  37. GRB 241030A: Swift-UVOT observations of the optical prompt flare
  38. EP241103A: LCO optical observations
  39. EP241103a: an X-ray transient detected by Einstein Probe
  40. GRB 241029A: GRBAlpha detection
  41. EP241101a: BOOTES-7 optical upper limit
  42. S241102cy: Identification of a GW compact binary merger candidate
  43. LIGO/Virgo/KAGRA S241102br: Identification of a GW compact binary merger candidate
  44. Kinder optical follow-up observations of EP241021a, EP241026b, and EP241030a/GRB241030A
  45. GRB241030A: OHP/T193 optical observations
  46. GRB 241101A: FRAM-ORM optical limit
  47. LIGO/Virgo/KAGRA S241101ee: Identification of a GW compact binary merger candidate
  48. GRB 241030A/EP241030a: TNOT observations of the optical counterpart
  49. EP241021a: Upper limit from Konus-Wind observations
  50. GRB 241030A: further SAO RAS optical observations
  51. GRB 241030A: Optical Observations via Virtual Telescope Project
  52. EP241021a: Liverpool Telescope optical follow-up observations
  53. GRB 241026A: SAO RAS optical observations
  54. GRB 241030B: NUTTelA-TAO / BSTI Optical Limits
  55. EP241021a: OHP/T193 optical observations
  56. GRB 241030A: Palomar 1-m telescope COSMOS optical observations
  57. GRB 241030B: Montarrenti Observatory optical upper limit
  58. EP241026b: Liverpool Telescope optical follow-up
  59. GRB 241030A: SAO RAS optical observations
  60. EP241021a: AMI-LA radio detection
  61. GRB 241030B : GIT optical upper limits
  62. GRB 241030B: LCOGT Optical Upper Limits
  63. GRB 241030A: Swift-BAT refined analysis
  64. GRB 241029A: COLIBRI Detection of the Optical Counterpart
  65. GRB 241030B: Swift/UVOT Detection
  66. GRB 241029A: LCO optical detection
  67. GRB 241030B: GTC/OSIRIS+ tentative spectroscopic redshift z = 2.82
  68. GRB 241030B : MITSuME Akeno optical upper limits
  69. GRB 241030A: COLIBRI Continuing Detection of the Afterglow
  70. GRB 241030B: SVOM/VT optical afterglow observations
  71. GRB 241030B: COLIBRÍ Upper Limits on the Optical Counterpart
  72. EP241030a: EP detection of GRB 241030A X-ray Afterglow
  73. GRB 241030B: BTA observations
  74. GRB 241029A: SVOM/VT optical afterglow observations
  75. GRB 241030B: Enhanced Swift-XRT position
  76. GRB241030B: GRANDMA/TAROT Upper Limit
  77. GRB 241030B: SAO RAS optical observations
  78. GRB 241030B: AKO Optical Afterglow Detection
  79. GRB 241030B: Nanshan/HMT optical afterglow detection
  80. Konus-Wind detection of GRB 241030A
  81. GRB 241030B: Swift detection of a burst
  82. GRB 240912A: radio detection with the VLA
  83. GRB 241030A: AKO Optical Afterglow Detection
  84. GRB 241030A: Swift/UVOT Detection
  85. GRB 241030A: SVOM/C-GFT optical observations
  86. GRB 241026A: LBT optical observations
  87. EP241021a: Optical rebrightening observations with Mephisto
  88. GRB 241030A: Multiband optical detection with Mephisto
  89. GRB 241030A: SVOM/VT optical afterglow observations
  90. GRB 241030A : MITSuME Akeno optical afterglow detection
  91. GRB 241030A: Enhanced Swift-XRT position
  92. GRB 241029A: GROWTH-India Telescope optical follow up
  93. GRB 241030A: ULL-ASTRO-MASTER detection of a bright optical counterpart with the LCOGT 40-cm telescope at McDonald Observatory
  94. GRB 241030A: COLIBRÍ Detection of the Bright Optical Counterpart
  95. GRB 241030A: Swift detection of a burst with a bright optical counterpart
  96. GRB 241029A: SAO RAS optical observations
  97. GRB 241026A: SAO RAS optical observations
  98. EP241021a: SAO RAS observations of rebrightening
  99. GRB 241029A: GTC/OSIRIS+ spectroscopic redshift z=1.072
  100. MISTRAL@OHP photometric and spectroscopic observations of GRB 241029A

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