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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"

32740 results found.

  1. GRB 241010A: host galaxy redshift z = 0.977
  2. EP241101a NUTTelA-TAO / BSTI Measurements 2024-11-02
  3. GRB 241104A : Detection and localization by SVOM/ECLAIRs
  4. GRB 240821A: further radio observations with the VLA
  5. Fermi GRB 241104A: Global MASTER-Net observations report
  6. GRB 241030A: GRBAlpha detection
  7. EP241101a: EP-FXT observations update
  8. EP241103a: GIT optical upper limit
  9. EP241021a: OHP/T193 further optical observations
  10. LIGO/Virgo/KAGRA S241102br: OHP/T193 optical observations
  11. LIGO/Virgo/KAGRA S241102cy: Updated Sky localization
  12. EP241103a: GOTO optical upper limit
  13. LIGO/Virgo/KAGRA S241102br: Updated Sky localization
  14. EP241101a: Possible detection of an optical counterpart with FTW
  15. EP241103a: Swift XRT detection and improved X-ray position
  16. EP241021a: continued SOAR observations
  17. EP241101a: Optical upper limits with Kinder observations
  18. EP241101a: OHP/T193 optical observations
  19. EP241103a: Gemini optical limits
  20. EP241103a: EP observation update
  21. LIGO/Virgo/KAGRA S241102br: EP-WXT X-ray follow-up and flux limits
  22. GRB 241030A: Swift-UVOT observations of the optical prompt flare
  23. EP241103a: GSP optical upper limit
  24. EP241103A: LCO optical observations
  25. EP241103a: Global MASTER-Net observations report
  26. GRB 241030A: Rapid release of TESS data.
  27. EP241101a: Global MASTER-Net observations report
  28. GRB 241029A: GRBAlpha detection
  29. LIGO/Virgo/KAGRA S241101ee: Updated Sky localization
  30. S241102cy: Identification of a GW compact binary merger candidate
  31. LIGO/Virgo/KAGRA S241102br: Identification of a GW compact binary merger candidate
  32. Kinder optical follow-up observations of EP241021a, EP241026b, and EP241030a/GRB241030A
  33. GRB241030A: OHP/T193 optical observations
  34. EP241030a: Futher EP-FXT observation of the X-ray Afterglow of GRB 241030A
  35. Swift GRB 241101A: Global MASTER-Net observations report
  36. LIGO/Virgo/KAGRA S241101ee: Identification of a GW compact binary merger candidate
  37. GRB 241030A/EP241030a: TNOT observations of the optical counterpart
  38. EP241021a: Upper limit from Konus-Wind observations
  39. GRB 241101A: Swift-BAT refined analysis
  40. GRB 241030A: further SAO RAS optical observations
  41. GRB 241030A: Optical Observations via Virtual Telescope Project
  42. EP241021a: Liverpool Telescope optical follow-up observations
  43. GRB 241026A: SAO RAS optical observations
  44. GRB 241030A / EP241030a: GMG possible spectroscopic redshift at z ~ 1.4
  45. EP241030a: EP/FXT observation of GRB 241030A X-ray Afterglow
  46. GRB 241030B: NUTTelA-TAO / BSTI Optical Limits (duplicate submission of 38023)
  47. GRB 241030B: NUTTelA-TAO / BSTI Optical Limits
  48. EP241021a: OHP/T193 optical observations
  49. GRB 241030A: Palomar 1-m telescope COSMOS optical observations
  50. GRB 241030B: Montarrenti Observatory optical upper limit
  51. GRB 241030A / EP241030a: FTW Optical and NIR observations of the optical counterpart
  52. EP241026b: Liverpool Telescope optical follow-up
  53. GRB 241030A: SAO RAS optical observations
  54. GRB 241030A: Fermi GBM Observation
  55. EP241021a: AMI-LA radio detection
  56. GRB 241030B : GIT optical upper limits
  57. GRB 241030B: LCOGT Optical Upper Limits
  58. GRB 241030B: Swift-BAT refined analysis
  59. GRB 241030A: Swift-BAT refined analysis
  60. GRB 241029A: COLIBRI Detection of the Optical Counterpart
  61. GRB 241030B: Swift/UVOT Detection
  62. EP EP241030a: Global MASTER-Net observations report
  63. GRB 241029A: LCO optical detection
  64. GRB 241030B: GTC/OSIRIS+ tentative spectroscopic redshift z = 2.82
  65. GRB 241030B: SVOM/GRM observation
  66. GRB 241030B : MITSuME Akeno optical upper limits
  67. GRB 241030A: COLIBRI Continuing Detection of the Afterglow
  68. GRB 241030B: SVOM/VT optical afterglow observations
  69. GRB 241030B: COLIBRÍ Upper Limits on the Optical Counterpart
  70. EP241030a: EP detection of GRB 241030A X-ray Afterglow
  71. GRB241030B: Fermi GBM Observation
  72. GRB 241030B: BTA observations
  73. GRB 241029A: SVOM/VT optical afterglow observations
  74. GRB 241030A: detection of the bright optical counterpart in ATLAS forced photometry
  75. GRB 241030B: optical observations from the INAF Asiago Observatory
  76. EP241021a: Swift-UVOT detection
  77. GRB241030B: GRANDMA/TAROT Upper Limit
  78. GRB 241030B: SAO RAS optical observations
  79. GRB 241030B: AKO Optical Afterglow Detection
  80. GRB 241030B: Nanshan/HMT optical afterglow detection
  81. GRB 241030B: SVOM/ECLAIRs detection of a burst
  82. Konus-Wind detection of GRB 241030A
  83. GRB 241030A: Fermi-LAT detection
  84. GRB 240912A: radio detection with the VLA
  85. Fermi GRB 241030A: Global MASTER-Net observations report
  86. GRB 241030A: AKO Optical Afterglow Detection
  87. Swift GRB 241030A: Global MASTER-Net observations report
  88. GRB 241030A: Swift/UVOT Detection
  89. EP 241021a: further Swift-XRT observations and X-ray counterpart detection
  90. GRB 241030A: SVOM/GRM observation
  91. GRB 241026A: Swift-BAT refined analysis
  92. GRB 241030A: SVOM/C-GFT optical observations
  93. GRB 241026A: LBT optical observations
  94. EP241021a: Optical rebrightening observations with Mephisto
  95. EP241026b: EP-FXT follow-up observation
  96. GRB 241030A: Multiband optical detection with Mephisto
  97. GRB 241030A: SVOM/VT optical afterglow observations
  98. GRB 241025A: The discovery of a BdHN I from data of Swift, Fermi, SVOM and Einstein Probe telescopes
  99. GRB 241030A : MITSuME Akeno optical afterglow detection
  100. GRB 241029A: GROWTH-India Telescope optical follow up

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