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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').
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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.

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subject:"Swift"
body:"GRB"
submitter:"Judith Racusin"

28301 results found.

  1. LIGO/Virgo/KAGRA S240621dy: Updated Sky localization and Source Classification
  2. LIGO/Virgo/KAGRA S240621eb: Updated Sky localization and Source Classification
  3. EP240618a: GSP optical upper limit
  4. LIGO/Virgo/KAGRA S240622h: Identification of a GW compact binary merger candidate
  5. LIGO/Virgo/KAGRA S240621em: Identification of a GW compact binary merger candidate
  6. LIGO/Virgo/KAGRA S240621eb: Identification of a GW compact binary merger candidate
  7. LIGO/Virgo/KAGRA S240621dy: Identification of a GW compact binary merger candidate
  8. GRB 240619C: NuSTAR automated detection of the GRB
  9. GRB 240619A: Fermi GBM Observation
  10. Fermi GBM Sub-Threshold Detection of GRB 240619C
  11. GRB 240615A: NOT optical observations
  12. GRB 240619C: AstroSat CZTI detection
  13. EP240618a: TRT optical upper limit
  14. EP240617a: STEP/T80S optical limits
  15. GRB 240615A: possible transient detection from Wendelstein observations
  16. LIGO/Virgo/KAGRA S240615dg: Updated Sky localization
  17. LIGO/Virgo/KAGRA S240618ah: Updated Sky localization
  18. EP240618a: OHP/T193 MISTRAL i' and Y band upper limits
  19. LIGO/Virgo S240615dg: Swift XRT observations, 39 X-ray sources
  20. GRB240615A: 1.3m DFOT optical upper limit
  21. GRB 240619A: BALROG localization (Fermi Trigger 740461416 / GRB 240619155)
  22. EP240617a: EP-WXT detection of a fast X-ray transient
  23. EP240618a: EP-WXT detection of a fast X-ray transient and EP-FXT quick follow-up
  24. LIGO/Virgo/KAGRA S240618ah: Identification of a GW compact binary merger candidate
  25. LIGO/Virgo/KAGRA S240615ea: Upper limits from Swift/BAT-GUANO
  26. LIGO/Virgo/KAGRA S240615dg: Upper limits from Swift/BAT-GUANO
  27. GRB 240615A: J-band upper limits from WINTER
  28. LIGO/Virgo/KAGRA S240615ea: Updated Sky localization
  29. GRB 240615A: Swift-XRT observations
  30. X-ray transient EP240414a: Chandra late time observation
  31. GRB 240615A: Swift/BAT-GUANO arcminute localization of a short burst
  32. LIGO/Virgo/KAGRA S240615ea: Identification of a GW compact binary merger candidate
  33. LIGO/Virgo/KAGRA S240615dg: Identification of a GW compact binary merger candidate
  34. GRB 240603A: VZLUSAT-2 detection
  35. EXO 0748-676: Swift-BAT refined analysis
  36. GRB240529A: 3.6m TNG NIR detection 8d after the burst
  37. GRB 240529A: LBT optical detection and late temporal decay
  38. GRB 240529A : MITSuME Akeno optical afterglow detection
  39. Trigger 1236151: Swift detection of EXO 0748-676
  40. IPN triangulation of GRB 240607A
  41. Fermi trigger No 739632045: Global MASTER-Net observations report
  42. GRB 240607A: Fermi GBM Observation
  43. GRB 240606B: Fermi GBM Observation
  44. Swift Trigger 1235109: consistent with noise and not astrophysical
  45. GRB 240607A: Fermi GBM detection of a very bright burst
  46. GRB 240529A: radio detection with AMI-LA
  47. GRB 240607A: BALROG localization (Fermi Trigger 739450879 / GRB 240607459)
  48. GRB 240606B: Swift-XRT afterglow detection
  49. GRB 240606B: Swift/BAT-GUANO arcminute localization of a burst
  50. Swift Trigger 1235109: a possible GRB 240606A
  51. LIGO/Virgo/KAGRA S240601co: Updated Sky localization
  52. GRB 240604A: GECAM detection of a long burst
  53. GRB 240529A: SAO RAS optical observations
  54. Swift Trigger 1232755: likely consistent with noise and not astrophysical
  55. LIGO/Virgo/KAGRA S240601co: Upper limits from Swift/BAT-GUANO
  56. LIGO/Virgo/KAGRA S240530a: Upper limits from Swift/BAT-GUANO
  57. GRB 240603C: BALROG localization (Fermi Trigger 739102156 / GRB 240603423)
  58. Swift Trigger 1232465: consistent with noise
  59. GRB 240529A: MASTER prompt OT detection
  60. GRB 240603A: GECAM detection of a short burst
  61. GRB 240529A: continued SAO RAS optical observations
  62. GRB 240529A: OSN optical detection
  63. The EP-WXT source triggered on June 1st is likely a flaring star
  64. GRB 240529A: further SAO RAS optical observations
  65. LIGO/Virgo/KAGRA S240601aj: Updated Sky localization
  66. LIGO/Virgo/KAGRA S240601co: Identification of a GW compact binary merger candidate
  67. Swift Trigger 1232465 is not a GRB
  68. GRB 240529A: AKO Optical Afterglow Follow-Up Observations
  69. LIGO/Virgo/KAGRA S240530a: Updated Sky localization
  70. LXT 240528A: GSP optical upper limit
  71. GRB 240529A: 1.3m DFOT Optical observations
  72. LIGO/Virgo/KAGRA S240527en: Updated Sky localization
  73. LIGO/Virgo/KAGRA S240601aj: Identification of a GW compact binary merger candidate
  74. GRB 240531A: AstroSat CZTI detection of a short burst
  75. GRB 240529A : Mondy optical observations
  76. GRB 240529A: SAO RAS optical observations
  77. LIGO/Virgo/KAGRA S240531bp: Updated Sky localization
  78. LIGO/Virgo/KAGRA S240531bp: Identification of a GW compact binary merger candidate
  79. GRB 240529A: GROWTH-India optical follow-up
  80. GRB 240529A: T193/MISTRAL observations
  81. GRB 240529A: Redshift from GTC/OSIRIS+
  82. GRB 240529A: AKO Optical Afterglow Detection
  83. LIGO/Virgo/KAGRA S240530a: Identification of a GW compact binary merger candidate
  84. LIGO/Virgo/KAGRA S240527fv: Upper limits from Swift/BAT-GUANO
  85. LIGO/Virgo/KAGRA S240525p: Upper limits from Swift/BAT-GUANO
  86. GRB 240529A: J-band detections with WINTER
  87. GRB 240529A: Skynet Optical Observations
  88. LXT 240528A: LEIA detection of a fast X-ray transient
  89. GRB 240529A: Swift-BAT refined analysis
  90. LIGO/Virgo S240527fv: GRANDMA/FRAM-Auger Optical Observations
  91. GRB 240529A: Swift-XRT refined Analysis
  92. GRB 240529A: Swift/UVOT Detection
  93. GRB 240529A: NOT optical observations
  94. GRB 240527B: Swift-XRT afterglow detection
  95. GRB 240529A: Enhanced Swift-XRT position
  96. GRB 240529A: Swift detection of a burst with an optical counterpart
  97. LIGO/Virgo/KAGRA S240527fv: Updated Sky localization
  98. GRB 240527B: Fermi GBM Observation
  99. LIGO/Virgo/KAGRA S240527fv: Identification of a GW compact binary merger candidate
  100. LIGO/Virgo/KAGRA S240527en: Identification of a GW compact binary merger candidate

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