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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"

43136 results found.

  1. EP241107a: SVOM/C-GFT optical observations
  2. EP241107a: AKO Optical Afterglow Detection
  3. GRB 241025A: LBT optical observations
  4. GRB241105A: Gemini-South Optical Afterglow Detection
  5. EP241107a: EP on-board trigger and autonomous follow-up observation
  6. GRB 241105A: VLT/FORS2 optical afterglow rapid fading
  7. GRB 241105A: Swift/UVOT Detection
  8. EP241101a: CrAO ZTSH optical observations
  9. GRB 241105A: Swift/BAT-GUANO refined analysis of short burst with extended emission
  10. GRB 241030A: optical afterglow detection from the INAF Asiago Observatory
  11. GRB 241105A: BOOTES-7 optical detection
  12. GRB 241030A: Mondy optical observations
  13. GRB 241105A: Fermi GBM Observation of a Short Burst with Extended Emission
  14. Konus-Wind detection of GRB 241105A (short with extended emission)
  15. LIGO/Virgo/KAGRA S241106ba: 1 counterpart neutrino candidate event from an IceCube neutrino search
  16. LIGO/Virgo/KAGRA S241102o: 1 counterpart neutrino candidate event from an IceCube neutrino search
  17. Konus-Wind detection of GRB 241021A
  18. GRB 241105A: SVOM/VT optical afterglow observations
  19. GRB 241105A: Swift-XRT afterglow detection
  20. GRB 241105A: VLT/FORS2 spectroscopic redshift z = 2.681
  21. GRB 241104A: Swift-XRT observations
  22. GRB 240511A: LCO upper limits
  23. GRB 241104A: Fermi GBM Observation
  24. GRB 241104A: The SVOM/VT candidate in GCN circular 38086 is not an astrophysical source
  25. GRB 241105A: Swift ToO observations
  26. GRB 241105A: Swift/BAT-GUANO arcminute localization of a short burst
  27. GRB 241104A: Swift ToO observations
  28. GRB 241104A: NOT optical non-detection
  29. GRB 241105A: GOTO tentative optical counterpart candidate
  30. Fermi GRB 241105A: Global MASTER-Net observations report
  31. GRB 241104A: SVOM/VT optical candidate
  32. GRB 241105A: Fermi GBM Final Real-time Localization
  33. GRB 241104A/EP241104a: Optical upper limits with Kinder observations
  34. GRB 241104A: COLIBRÍ Upper Limits on the Optical Counterpart
  35. GRB 241104A: SVOM/GRM observation
  36. EP241104a: EP detection of GRB 241104A X-ray emission
  37. GRB 241010A: host galaxy redshift z = 0.977
  38. EP241101a NUTTelA-TAO / BSTI Measurements 2024-11-02
  39. GRB 241104A : Detection and localization by SVOM/ECLAIRs
  40. GRB 240821A: further radio observations with the VLA
  41. Fermi GRB 241104A: Global MASTER-Net observations report
  42. GRB 241104A: Fermi GBM Final Real-time Localization
  43. GRB 241030A: GRBAlpha detection
  44. EP241101a: EP-FXT observations update
  45. EP241103a: GIT optical upper limit
  46. EP241021a: OHP/T193 further optical observations
  47. LIGO/Virgo/KAGRA S241104a: Retraction of GW compact binary merger candidate
  48. Fermi trigger No 752365806: Global MASTER-Net observations report
  49. LIGO/Virgo/KAGRA S241102br: OHP/T193 optical observations
  50. LIGO/Virgo/KAGRA S241102cy: Updated Sky localization
  51. EP241103a: GOTO optical upper limit
  52. LIGO/Virgo/KAGRA S241102br: Updated Sky localization
  53. EP241101a: Possible detection of an optical counterpart with FTW
  54. EP241103a: Swift XRT detection and improved X-ray position
  55. EP241021a: continued SOAR observations
  56. EP241101a: Optical upper limits with Kinder observations
  57. EP241101a: OHP/T193 optical observations
  58. EP241103a: Gemini optical limits
  59. EP241103a: EP observation update
  60. LIGO/Virgo/KAGRA S241102br: MASTER observations and OT detection
  61. LIGO/Virgo/KAGRA S241102br: EP-WXT X-ray follow-up and flux limits
  62. GRB 241030A: Swift-UVOT observations of the optical prompt flare
  63. EP241103a: GSP optical upper limit
  64. EP241103A: LCO optical observations
  65. EP241103a: Global MASTER-Net observations report
  66. EP241103a: an X-ray transient detected by Einstein Probe
  67. GRB 241030A: Rapid release of TESS data.
  68. EP241101a: Global MASTER-Net observations report
  69. GRB 241029A: GRBAlpha detection
  70. EP241101a: BOOTES-7 optical upper limit
  71. LIGO/Virgo/KAGRA S241101ee: Updated Sky localization
  72. S241102cy: Identification of a GW compact binary merger candidate
  73. LIGO/Virgo/KAGRA S241102br: NED Galaxies in the Localization Volume
  74. LIGO/Virgo/KAGRA S241102br: Identification of a GW compact binary merger candidate
  75. Kinder optical follow-up observations of EP241021a, EP241026b, and EP241030a/GRB241030A
  76. GRB241030A: OHP/T193 optical observations
  77. EP241030a: Futher EP-FXT observation of the X-ray Afterglow of GRB 241030A
  78. EP241101a: EP-WXT detection of a fast X-ray transient
  79. Swift GRB 241101A: Global MASTER-Net observations report
  80. GRB 241101A: FRAM-ORM optical limit
  81. LIGO/Virgo/KAGRA S241101ee: Identification of a GW compact binary merger candidate
  82. GRB 241030A/EP241030a: TNOT observations of the optical counterpart
  83. EP241021a: Upper limit from Konus-Wind observations
  84. GRB 241101A: Swift-BAT refined analysis
  85. GRB 241030A: further SAO RAS optical observations
  86. GRB 241030A: Optical Observations via Virtual Telescope Project
  87. EP241021a: Liverpool Telescope optical follow-up observations
  88. GRB 241026A: SAO RAS optical observations
  89. GRB 241030A / EP241030a: GMG possible spectroscopic redshift at z ~ 1.4
  90. EP241030a: EP/FXT observation of GRB 241030A X-ray Afterglow
  91. GRB 241101A: Swift detection of a burst
  92. GRB 241030B: NUTTelA-TAO / BSTI Optical Limits
  93. EP241021a: OHP/T193 optical observations
  94. GRB 241030A: Palomar 1-m telescope COSMOS optical observations
  95. GRB 241030B: Montarrenti Observatory optical upper limit
  96. GRB 241030A / EP241030a: FTW Optical and NIR observations of the optical counterpart
  97. EP241026b: Liverpool Telescope optical follow-up
  98. Fermi trigger No 752083996: Global MASTER-Net observations report
  99. GRB 241030A: SAO RAS optical observations
  100. GRB 241030A: Fermi GBM Observation

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