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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"

32689 results found.

  1. LIGO/Virgo/KAGRA S230518h: Updated Sky localization
  2. LIGO/Virgo/KAGRA S230520ae: Updated Sky localization
  3. Fermi-LAT gamma-ray observations of IceCube-230524A
  4. LIGO/Virgo/KAGRA S230518h: Upper limits from Glowbug gamma-ray observations
  5. GRB 230510A: Swift-BAT refined analysis
  6. GRB 230525A: Fermi GBM Detection
  7. LIGO/Virgo/KAGRA S230518h: TESS observations of the localization region
  8. GRB 230523B: GRBAlpha detection
  9. GRB 230524A: Fermi GBM Observation
  10. GRB 230524A: AstroSat CZTI detection
  11. GRB 230524A: AGILE detection
  12. LIGO/Virgo/KAGRA S230521k: MASTER new OT discovery
  13. GRB 230523B: Name correction from GCN Circular 33859
  14. LIGO/Virgo/KAGRA S230521k: Additional candidates from Zwicky Transient Facility
  15. LIGO/Virgo/KAGRA S230518h: Swift/UVOT Upper Limits for MeerLICHT candidates: AT2023ixg and AT2023iyb
  16. GRB 230518B: VZLUSAT-2 detection
  17. Fermi Gamma-ray Burst Monitor trigger 706338208/230521211 is not a GRB
  18. IPN triangulation of GRB 230518A (short)
  19. GRB 230520A: CALET Gamma-Ray Burst Monitor detection
  20. LIGO/Virgo/KAGRA S230520ae: Identification of a GW compact binary merger candidate: End-to-End Test
  21. GRB 230520B is not a GRB
  22. LIGO/Virgo/KAGRA S230518h: ATCA follow-up of candidate counterparts
  23. LIGO/Virgo/KAGRA S230518h: GECKO tiling observations with KMTNet
  24. LIGO/Virgo/KAGRA S230518h: Swift/UVOT Upper Limits for Swope candidates: SSS23a, SSS23b and SSS23c
  25. LIGO/Virgo/KAGRA S230518h: ATLAS observations of the skymap
  26. LIGO/Virgo/KAGRA S230518h: Swope Search and Candidate Counterpart Identification
  27. GRB 230518A: Fermi GBM Observation
  28. LIGO/Virgo/KAGRA S230518h: Upper limits from Konus-Wind observations
  29. GRB 230518A: Swift/BAT-GUANO detection
  30. LIGO/Virgo/KAGRA S230518h: Coverage and upper limits from MAXI/GSC observations
  31. LIGO/Virgo/KAGRA S230518h: AstroSat CZTI non-detection and upper limits
  32. LIGO/Virgo/KAGRA S230518h: Upper limits from Fermi-GBM Observations
  33. LIGO/Virgo/KAGRA S230518h: Updated Sky localization and EM Bright Classification
  34. LIGO/Virgo S230518h: No counterpart candidates in INTEGRAL SPI-ACS prompt observation
  35. LIGO/Virgo/KAGRA S230518h: Identification of a GW compact binary merger candidate
  36. GRB 230513A: Zwicky Transient Facility continuous observations of a Fermi Short GRB (Trigger 705709044)
  37. GRB 230510B: GRBAlpha detection
  38. Improved IPN triangulation of GRB 230512A
  39. GRB 230510B: Fermi GBM detection
  40. IPN triangulation of GRB 230511D (short)
  41. IPN triangulation of GRB 230512A
  42. GRB 230513A: Zwicky Transient Facility Follow-Up of a Fermi Short GRB (Trigger 705709044)
  43. GRB 230512A: Nanshan/NEXT non-detection of GRB afterglow candidate
  44. GRB 230512A: Zwicky Transient Facility non-detection of GRB afterglow candidate
  45. GRB 230512A: Liverpool Telescope observations
  46. GRB 230512A: GIT non detection of afterglow candidate
  47. GRB 230512A: Kitab possible afterglow candidate
  48. GRB 230512A: GRBAlpha detection
  49. GRB 230510A: GRBAlpha detection
  50. Fermi-LAT gamma-ray observations of IceCube-230511A
  51. GRB 230510A: OHP/T193 and OHP/T120 optical observations
  52. IceCube-230511A: Upper limits from a search for additional neutrino events in IceCube
  53. GRB 230512A: GIT optical follow-up ZTF candidates
  54. GRB 230512A: Fermi GBM detection
  55. GRB 230512A: Zwicky Transient Facility Follow-Up of a Fermi Short GRB (Trigger 705565670)
  56. GRB 230430A: Zwicky Transient Facility Follow-Up of a Fermi Short GRB (Trigger 704533643)
  57. GRB 230512A: Tiled Swift observations
  58. GRB 230512A: Fermi-LAT detection
  59. GRB 230512A: AstroSat CZTI detection
  60. GRB 230510A: GIT optical upper limits
  61. GRB 230510A: LCOGT Optical Upper Limit
  62. GRB 230510A: Swift/UVOT Observations
  63. GRB 230510B: AstroSat CZTI detection
  64. GRB 230510A: Fermi GBM detection
  65. GRB 230510A: Gaoyazi/GOT optical upper limit
  66. GRB 230510B: CALET Gamma-Ray Burst Monitor detection
  67. GRB 230510A: CALET Gamma-Ray Burst Monitor detection
  68. GRB 230510A: Nanshan/NEXT optical afterglow detection
  69. GRB 230510B: MAXI/GSC detection
  70. GRB 230506B: Fermi GBM detection
  71. GRB 230506C: Fermi GBM detection
  72. GRB 230506C: T193-OHP MISTRAL tentative redshift
  73. GRB 230506C: SAO RAS optical observations
  74. GRB 230307A: JWST second-epoch observations
  75. IceCube-230506A: Upper limits from a search for additional neutrino events in IceCube
  76. Fermi-LAT gamma-ray observations of IceCube-230506A
  77. GRB 230506C: Swift-BAT refined analysis
  78. GRB 230506B: Swift-BAT refined analysis
  79. GRB 230506C: spectro-imaging observations of the optical afterglow with T193-OHP
  80. GRB 230506B: LCOGT Optical Upper Limits
  81. GRB 230506C: Swift/UVOT Upper Limits
  82. GRB 230506C: NUTTelA-TAO / BSTI Early Optical Limits
  83. GRB 230506C: TSHAO possible afterglow candidate
  84. GRB 230506B: Swift/UVOT Detection
  85. GRB 230506B: Swift detection of a burst
  86. GRB 230506B: MASTER optical observations
  87. GRB 230506B: Swift detection of a burst
  88. GRB 230420A: Mondy optical afterglow detection, TSHAO, CrAO optical upper limit
  89. GRB 230427A: Swift-BAT refined analysis
  90. Konus-Wind detection of GRB 230430A
  91. IPN triangulation of GRB 230430A (short)
  92. GRB 230420A: AROMA-N Optical Upper Limit
  93. GRB 230430A: Fermi GBM observation
  94. GRB 230430A: AstroSat CZTI detection
  95. GRB 230427A: NOT optical upper limit
  96. GRB 230427A: TSHAO, SAO RAS, AbAO optical upper limit
  97. GRB 230427A: Swift/UVOT Detection
  98. Duplicate of GCN 33369
  99. GRB 230427A: Gaoyazi/GOT optical upper limit
  100. GRB 230427A: OHP/T193 spectroscopy observations of WISEA J101316.01+481158.7

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