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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"

20550 results found.

  1. EP241119a: EP detection of a fast X-ray transient
  2. GRB241120A: a long GRB detected by INTEGRAL
  3. GRB 241112B: Mephisto further optical observations
  4. GRB 241030A: J-band observations
  5. GRB 241115a: PRIME near-infrared upper limits
  6. GRB 241117A: Swift/BAT-GUANO localization skymap of a burst
  7. GRB 241117A: SVOM/GRM observation of a short burst with extended emission
  8. IceCube-Cascade 241116A: Upper limits from a search for additional neutrino events in IceCube
  9. GRB 241115B: Swift/BAT-GUANO localization skymap of a long burst
  10. GRB 241115A: Swift-XRT afterglow detection
  11. LIGO/Virgo/KAGRA S241116cq: Identification of a GW compact binary merger candidate
  12. EP241115a/GRB 241115D: Optical upper limits with Kinder observations
  13. GRB 241115A: Mephisto upper limits
  14. GRB 241113B: Mephisto upper limits
  15. EP241115a/GRB 241115D: Swift/XRT follow-up observation
  16. GRB 241115D / EP 241115a: SVOM/GRM observation
  17. The EP-WXT trigger 01709120856 is likely a flaring star
  18. EP241113a: Swift XRT weak detection
  19. GRB 241115A: LCOGT Optical Upper Limits
  20. GRB 241115C: Swift/BAT-GUANO localization skymap of a burst
  21. EP241115a: EP detection of a fast X-ray transient
  22. GRB 241115A: Swift detection of a burst
  23. EP 241113a: LBT possible optical counterpart
  24. LIGO/Virgo/KAGRA S241114bi: Identification of a GW compact binary merger candidate
  25. GRB 241113A: PRIME near-infrared upper limits
  26. GRB 241113B: J-band upper limit from WINTER
  27. GRB 241113A: J-band observations with WINTER
  28. EP241113a : J-band observations with WINTER
  29. GRB 241030A: LCO optical observation
  30. GRB 241113B: Swift-XRT observations
  31. IceCube-241113A: Upper limits from a search for additional neutrino events in IceCube
  32. GRB 241113A: 1.6m Mephisto and 50cm array optical upper limits
  33. EP241113b/GRB 241113B: EP detection of GRB 241113B
  34. EP241113a: EP on-board trigger and autonomous follow-up observation
  35. LIGO/Virgo/KAGRA S241114y: Identification of a GW compact binary merger candidate
  36. GRB 241113A: Swift/UVOT Detection
  37. GRB 241113A: REM detection of the optical/NIR afterglow
  38. GRB 241113A: LCO optical observations
  39. GRB 241112B: GMG Optical Upper Limit
  40. GRB 241113A: Enhanced Swift-XRT position
  41. GRB241113A: LCOGT (40-cm) optical counterpart detection
  42. GRB 241113A: Swift detection of a burst with an optical counterpart
  43. SVOM/GRM detection of a short burst from SGR 1E1841-045
  44. GRB 241112B: AbAO optical upper limit
  45. GRB 241107A: GROWTH-India telescope optical upper limit
  46. GRB 241112B: Optical afterglow detection confirmation in revisiting the Mephisto data
  47. GRB 241112B: LCO optical detection of the SVOM/VT candidate
  48. GRB 241107A: Swift/BAT candidate arcminute localization of a short burst
  49. GRB 241112B: Mephisto optical upper limits
  50. GRB 241112B: GOTO optical upper limits
  51. GRB 241107A: INTEGRAL IBIS localization
  52. EP241107a: EP-FXT follow-up observations
  53. LIGO/Virgo/KAGRA S241110br: NED Galaxies in the Localization Volume
  54. LIGO/Virgo/KAGRA S241109bn: ATLAS observations and discovery of the potential counterpart AT2024aawt
  55. LIGO/Virgo/KAGRA S241111bn: Identification of a GW compact binary merger candidate
  56. IPN triangulation of GRB 241107A (short/hard)
  57. GRB 241030B: TESS detection of optical counterpart
  58. LIGO/Virgo/KAGRA S241110br: Identification of a GW compact binary merger candidate
  59. LIGO/Virgo/KAGRA S241109bn: Upper limits from EP-WXT observations
  60. LIGO/Virgo/KAGRA S241109bn: Coverage and upper limits from MAXI/GSC observations
  61. EP241107a: AbAO optical upper limit
  62. GRB 241108A: Further COLIBRÍ Upper Limits on the Optical Counterpart
  63. LIGO/Virgo/KAGRA S241109bn: Identification of a GW compact binary merger candidate
  64. EP241107a: KAIT optical observations
  65. GRB 241108A: COLIBRÍ Upper Limits on the Optical Counterpart
  66. EP241107a: Kinder optical follow-up observations
  67. GRB 241025A: radio detection with the VLA
  68. EP241107a: AKO Optical Afterglow Follow-Up Observations
  69. GRB 241105A: SVOM/GRM observation
  70. EP241107a: OHP/T193 photometric and spectroscopic observations
  71. GRB 241105a: PRIME near-infrared upper limits
  72. GRB 241105A: ePESSTO+ NTT optical afterglow detection
  73. EP241107a: GIT optical observations
  74. EP241107a: SVOM/C-GFT optical observations
  75. EP241107a: AKO Optical Afterglow Detection
  76. GRB 241025A: LBT optical observations
  77. EP241107a: EP on-board trigger and autonomous follow-up observation
  78. GRB 241105A: VLT/FORS2 optical afterglow rapid fading
  79. GRB 241105A: Swift/UVOT Detection
  80. Konus-Wind detection of GRB 241105A (short with extended emission)
  81. Konus-Wind detection of GRB 241021A
  82. GRB 241105A: Swift-XRT afterglow detection
  83. GRB 241104A: Swift-XRT observations
  84. GRB 240511A: LCO upper limits
  85. GRB 241104A: SVOM/VT optical candidate
  86. GRB 241104A/EP241104a: Optical upper limits with Kinder observations
  87. GRB 241104A: COLIBRÍ Upper Limits on the Optical Counterpart
  88. EP241104a: EP detection of GRB 241104A X-ray emission
  89. GRB 241010A: host galaxy redshift z = 0.977
  90. EP241101a NUTTelA-TAO / BSTI Measurements 2024-11-02
  91. GRB 240821A: further radio observations with the VLA
  92. GRB 241104A: Fermi GBM Final Real-time Localization
  93. EP241103a: GIT optical upper limit
  94. EP241021a: OHP/T193 further optical observations
  95. LIGO/Virgo/KAGRA S241102br: OHP/T193 optical observations
  96. EP241103a: Swift XRT detection and improved X-ray position
  97. EP241021a: continued SOAR observations
  98. EP241101a: Optical upper limits with Kinder observations
  99. EP241101a: OHP/T193 optical observations
  100. EP241103a: EP observation update

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