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GCN Circulars

GCN Circulars are rapid astronomical bulletins submitted by and distributed to community members worldwide. They are used to share discoveries, observations, quantitative near-term predictions, requests for follow-up observations, or future observing plans related to high-energy, multi-messenger, and variable or transient astrophysical events. 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"

24603 results found.

  1. LIGO/Virgo/KAGRA S230927l: Identification of a GW compact binary merger candidate
  2. LIGO/Virgo/KAGRA S230922q: Updated Sky localization
  3. LIGO/Virgo/KAGRA S230924an: Upper limits from Swift/BAT-GUANO
  4. LIGO/Virgo/KAGRA S230920al: Upper limits from Swift/BAT-GUANO
  5. Title: LIGO/Virgo/KAGRA S230919bj: Upper limits from Swift/BAT-GUANO
  6. LIGO/Virgo/KAGRA S230922g: DECam GW-MMADS candidates
  7. GRB 230812B: r'-band observations from MISTRAL at Observatoire de Haute-Provence
  8. LIGO/Virgo/KAGRA S230924an: Updated Sky localization
  9. LIGO/Virgo/KAGRA S230924an: Identification of a GW compact binary merger candidate
  10. LIGO/Virgo/KAGRA S230917af: GRAWITA wide-field observations
  11. LIGO/Virgo/KAGRA S230922g: Updated Sky localization
  12. LIGO/Virgo/KAGRA S230922g: Identification of a GW compact binary merger candidate
  13. LIGO/Virgo/KAGRA S230922q: Identification of a GW compact binary merger candidate
  14. LIGO/Virgo/KAGRA S230917af: Zwicky Transient Facility observations
  15. IPN triangulation of GRB 230919A (short)
  16. LIGO/Virgo/KAGRA S230904n: Classification of the candidate AT2023rkw with DBSP
  17. Fermi GBM Statement for Trigger 716527670/230916144
  18. GRB 230919A: Swift/BAT-GUANO detection of a possibly short burst outside the coded FOV
  19. LIGO/Virgo/KAGRA S230920al: Updated Sky localization
  20. LIGO/Virgo/KAGRA S230919bj: Updated Sky localization
  21. transient AT2023sva: imaging and spectroscopic observations from MISTRAL at Observatoire de Haute-Provence
  22. GRB 230812B : optical observations from MISTRAL at Observatoire de Haute-Provence
  23. GRB 230919A: AstroSat CZTI detection
  24. LIGO/Virgo/KAGRA S230920al: Identification of a GW compact binary merger candidate
  25. LIGO/Virgo/KAGRA S230919bj: Identification of a GW compact binary merger candidate
  26. GRB 230918B: GOTO detection of a fast-rising transient in the GBM localisation region
  27. LIGO/Virgo S230917af: Swift XRT observations, 6 X-ray sources
  28. GRB 230918A (short): Glowbug gamma-ray detection
  29. GRB 230916B: Glowbug gamma-ray detection
  30. GRB 230915A: Fermi GBM observation
  31. GRB 230812B: Radio observations with the uGMRT
  32. LIGO/Virgo/KAGRA S230917af: MAXI/GSC observations
  33. GRB 230915B: Glowbug gamma-ray detection
  34. GRB 230916A: NuSTAR Discovery of Prompt Emission from a Potential GRB
  35. GRB 230911A: Fermi GBM Observation
  36. LIGO/Virgo/KAGRA S230904n: Correction of the coordinates of the ZTF candidate counterpart
  37. Fermi-LAT gamma-ray observations of IceCube-230914A
  38. GRB 230915A: Swift/BAT-GUANO detection of a burst
  39. LIGO/Virgo/KAGRA S230914ak: Upper limits from Swift/BAT-GUANO
  40. Swift Triggers 1192234, 1192235 and 1192236 are not astrophysical events
  41. IceCube-230914A: Upper limits from a search for additional neutrino events in IceCube
  42. GRB 230911A: Swift-XRT afterglow detection
  43. Swift Trigger 1192088 is not an astrophysical event
  44. GRB 230913A: Glowbug gamma-ray detection
  45. LIGO/Virgo/KAGRA S230914ak: Updated Sky localization
  46. LIGO/Virgo/KAGRA S230914ak: Identification of a GW compact binary merger candidate
  47. GRB 230913A: Fermi GBM Observation
  48. LIGO/Virgo/KAGRA S230904n: One ZTF candidate counterpart to coincident neutrino event
  49. Swift Trigger 1191903 is not an astrophysical event
  50. GRB 230913A: Swift/BAT-GUANO arcminute localization of a burst
  51. GRB 230911A: GOTO optical counterpart candidate
  52. GRB 230911D: NuSTAR Detection of Prompt Emission
  53. GRB 230911C: Swift-XRT refined Analysis
  54. GRB 230911C: Swift-BAT refined analysis
  55. LIGO/Virgo/KAGRA S230911ae: Updated Sky localization
  56. GRB 230911D: Fermi GBM observation
  57. IPN triangulation of GRB 230911D (long)
  58. GRB230911C: LCOGT Optical Upper Limits
  59. LIGO/Virgo/KAGRA S230911ae: Identification of a GW compact binary merger candidate
  60. GRB 230911C: Swift/UVOT Upper Limits
  61. GRB 230911B: GRBAlpha and VZLUSAT-2 joint detection
  62. Fermi trigger No 716145795: Global MASTER-Net observations report
  63. GRB 230908A: Swift/BAT-GUANO detection of a long burst outside the coded FOV
  64. GRB 230911C: Enhanced Swift-XRT position
  65. GRB 230911D: BALROG localization (Fermi Trigger 716111594/ GRB 230911329)
  66. GRB 230911C: Swift detection of a burst
  67. GRB 230906A: BlackGEM upper limits
  68. GRB 230903A: TESS observations of optical emission
  69. GRB 230906A: AstroSat CZTI detection
  70. LIGO/Virgo/KAGRA S230908b: one counterpart neutrino candidate from IceCube neutrino searches
  71. Glowbug gamma-ray detection GRB 230905B
  72. GRB 230906A: Swift/UVOT Upper Limits
  73. GRB 230818A: radio observation with the VLA
  74. GRB 230205A: LBT spectroscopy of two host galaxy candidates
  75. GRB 230906A: Swift-XRT observations
  76. GRB 230812B: Chandra late-time detection of the X-ray afterglow
  77. GRB 230905B: GECAM-C detection of a long burst
  78. LIGO/Virgo/KAGRA S230904n: Updated Sky localization and EM Bright Classification
  79. LIGO/Virgo/KAGRA S230819ax: Correction to PROB_BBH and PROB_TERRES probabilities
  80. GRB 230903A: Swift-XRT refined Analysis
  81. GRB 230903A: Enhanced Swift-XRT position
  82. GRB 230903A: VLT/X-shooter optical observations
  83. GRB 230903A: Swift-BAT refined analysis
  84. Fermi trigger No 715429986: Global MASTER-Net observations report
  85. GRB 230903A: Fermi GBM detection
  86. LIGO/Virgo/KAGRA S230904n: 1 counterpart neutrino candidate from IceCube neutrino searches
  87. GRB 230904B: BALROG localization (Fermi Trigger 715526984 / GRB 230904562)
  88. LIGO/Virgo/KAGRA S230904n: Identification of a GW compact binary merger candidate
  89. GRB 230903A: LCOGT Optical Upper Limits
  90. GRB 230903A: Swift detection of a burst
  91. LIGO/Virgo/KAGRA S230831e: Updated Sky localization
  92. LIGO/Virgo/KAGRA S230831e: Identification of a GW compact binary merger candidate
  93. GRB 230827B: Glowbug gamma-ray detection
  94. GRB 230827A: Glowbug gamma-ray detection
  95. GRB 230826A: Glowbug gamma-ray detection
  96. GRB 230827B: Swift-XRT afterglow detection
  97. LIGO/Virgo/KAGRA S230820bq: Updated Sky localization
  98. LIGO/Virgo/KAGRA S230814ah: Updated Sky localization
  99. GRB 230827A: Fermi GBM Observation
  100. GRB 230826A: Swift-BAT refined analysis

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