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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"

18534 results found.

  1. GRB 241030A: J-band observations
  2. GRB 241115a: PRIME near-infrared upper limits
  3. GRB 241117A: Swift/BAT-GUANO localization skymap of a burst
  4. GRB 241117A: SVOM/GRM observation of a short burst with extended emission
  5. GRB 241115B: Swift/BAT-GUANO localization skymap of a long burst
  6. GRB 241115A: Swift-XRT afterglow detection
  7. EP241115a/GRB 241115D: Optical upper limits with Kinder observations
  8. GRB 241115A: Mephisto upper limits
  9. GRB 241113B: Mephisto upper limits
  10. EP241115a/GRB 241115D: Swift/XRT follow-up observation
  11. GRB 241115D / EP 241115a: SVOM/GRM observation
  12. The EP-WXT trigger 01709120856 is likely a flaring star
  13. EP241113a: Swift XRT weak detection
  14. GRB 241115A: Fermi GBM Observation
  15. GRB 241115A: LCOGT Optical Upper Limits
  16. GRB 241115C: Swift/BAT-GUANO localization skymap of a burst
  17. EP241115a: EP detection of a fast X-ray transient
  18. GRB 241115A: Swift detection of a burst
  19. EP 241113a: LBT possible optical counterpart
  20. LIGO/Virgo/KAGRA S241114bi: Identification of a GW compact binary merger candidate
  21. GRB 241113A: PRIME near-infrared upper limits
  22. GRB 241113B: J-band upper limit from WINTER
  23. GRB 241113A: J-band observations with WINTER
  24. EP241113a : J-band observations with WINTER
  25. GRB 241030A: LCO optical observation
  26. GRB 241113B: Swift-XRT observations
  27. GRB 241113A: 1.6m Mephisto and 50cm array optical upper limits
  28. EP241113b/GRB 241113B: EP detection of GRB 241113B
  29. EP241113a: EP on-board trigger and autonomous follow-up observation
  30. GRB 241113A: Swift/UVOT Detection
  31. GRB 241113A: REM detection of the optical/NIR afterglow
  32. GRB 241113A: LCO optical observations
  33. GRB 241112B: GMG Optical Upper Limit
  34. GRB 241113A: Enhanced Swift-XRT position
  35. GRB241113A: LCOGT (40-cm) optical counterpart detection
  36. GRB 241113A: Swift detection of a burst with an optical counterpart
  37. SVOM/GRM detection of a short burst from SGR 1E1841-045
  38. GRB 241105A: ATCA Radio Upper Limits
  39. GRB 241112B: AbAO optical upper limit
  40. GRB 241107A: GROWTH-India telescope optical upper limit
  41. GRB 241112B: Optical afterglow detection confirmation in revisiting the Mephisto data
  42. GRB 241112B: Swift-XRT afterglow detection
  43. GRB 241112B: LCO optical detection of the SVOM/VT candidate
  44. GRB 241112B: Mephisto optical upper limits
  45. GRB 241112B: GOTO optical upper limits
  46. GRB 241107A: INTEGRAL IBIS localization
  47. EP241107a: EP-FXT follow-up observations
  48. LIGO/Virgo/KAGRA S241109bn: ATLAS observations and discovery of the potential counterpart AT2024aawt
  49. IPN triangulation of GRB 241107A (short/hard)
  50. LIGO/Virgo/KAGRA S241109bn: Upper limits from EP-WXT observations
  51. LIGO/Virgo/KAGRA S241109bn: Coverage and upper limits from MAXI/GSC observations
  52. INTEGRAL detection of a burst from 1E 1841-045
  53. EP241107a: AbAO optical upper limit
  54. GRB 241108A: Further COLIBRÍ Upper Limits on the Optical Counterpart
  55. EP241109a: confirmation of a stellar flare by BOOTES-7
  56. EP241109a: EP on-board trigger and autonomous follow-up observation
  57. EP241107A: MASTER optical observations of xray transient
  58. EP241107a: KAIT optical observations
  59. GRB 241108A: COLIBRÍ Upper Limits on the Optical Counterpart
  60. EP241107a: Kinder optical follow-up observations
  61. GRB 241025A: radio detection with the VLA
  62. EP241107a: AKO Optical Afterglow Follow-Up Observations
  63. GRB 241105A: EP-FXT follow-up observations
  64. GRB 241105A: SVOM/GRM observation
  65. EP241107a: OHP/T193 photometric and spectroscopic observations
  66. GRB 241105a: PRIME near-infrared upper limits
  67. GRB 241105A: ePESSTO+ NTT optical afterglow detection
  68. EP241107a: GIT optical observations
  69. EP241107a: SVOM/C-GFT optical observations
  70. EP241107a: AKO Optical Afterglow Detection
  71. GRB 241025A: LBT optical observations
  72. EP241107a: EP on-board trigger and autonomous follow-up observation
  73. GRB 241105A: VLT/FORS2 optical afterglow rapid fading
  74. GRB 241105A: Swift/UVOT Detection
  75. GRB 241105A: Swift-XRT afterglow detection
  76. GRB 241104A: Swift-XRT observations
  77. GRB 240511A: LCO upper limits
  78. GRB 241104A: SVOM/VT optical candidate
  79. GRB 241104A/EP241104a: Optical upper limits with Kinder observations
  80. GRB 241104A: COLIBRÍ Upper Limits on the Optical Counterpart
  81. EP241104a: EP detection of GRB 241104A X-ray emission
  82. GRB 241010A: host galaxy redshift z = 0.977
  83. EP241101a NUTTelA-TAO / BSTI Measurements 2024-11-02
  84. GRB 240821A: further radio observations with the VLA
  85. EP241101a: EP-FXT observations update
  86. EP241103a: GIT optical upper limit
  87. EP241021a: OHP/T193 further optical observations
  88. LIGO/Virgo/KAGRA S241102br: OHP/T193 optical observations
  89. EP241103a: Swift XRT detection and improved X-ray position
  90. EP241021a: continued SOAR observations
  91. EP241101a: Optical upper limits with Kinder observations
  92. EP241101a: OHP/T193 optical observations
  93. EP241103a: EP observation update
  94. LIGO/Virgo/KAGRA S241102br: EP-WXT X-ray follow-up and flux limits
  95. GRB 241030A: Swift-UVOT observations of the optical prompt flare
  96. EP241103A: LCO optical observations
  97. EP241103a: an X-ray transient detected by Einstein Probe
  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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