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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.

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

14931 results found.

  1. GRB 190507A: Fermi GBM Final Real-time Localization
  2. Update to the Fermi GBM GCN Reporting
  3. IceCube-190504A: Insight-HXMT/HE observation
  4. GRB 190501A: CALET Gamma-Ray Burst Monitor detection
  5. Search for counterpart to IceCube-190504A with ANTARES
  6. IceCube-190503A: Insight-HXMT/HE observation
  7. LIGO/Virgo S190503bf: Swift/BAT Counterpart Search
  8. LIGO/Virgo S190503bf: Insight-HXMT/HE observation
  9. IceCube-190503A: Insight-HXMT/HE observation
  10. LIGO/Virgo S190503bf: Fermi-GBM Observations
  11. Correction in name: GRB 190501B (not GRB 190501BA) : AstroSat CZTI detection
  12. GRB 190501B: AstroSat CZTI detection
  13. IPN Triangulation of GRB 190501A (long/bright)
  14. GRB 190501A: GOTO optical counterpart search
  15. LIGO/Virgo S190425z: Insight-HXMT observation and counterpart search
  16. LIGO/Virgo S190426c: Gaia19boq 0.6m BOOTES-5/JGT, 1.5m OSN and 10.4m GTC observations
  17. GRB 190501A: refined position from AGILE/GRID analysis
  18. GRB 190501A: AGILE/GRID detection
  19. GRB 190501A: AGILE/MCAL and scientific ratemeters detection of a burst
  20. LIGO/Virgo S190426c: ZTF19aaslzjf, ZTF19aasmftm and ZTF19aasmddt 1.5m OSN and 10.4m GTC observations
  21. GRB 190429A: AstroSat CZTI detection
  22. GRB 190427A: CALET Gamma-Ray Burst Monitor detection
  23. LIGO/Virgo S190425z: MASTER detection of the faint flare in SDSS Seyfert galaxy z = 0.09
  24. LIGO/Virgo S190425z: DECam Observations of the UVOT Candidate Region
  25. LIGO/Virgo S190425z: RATIR non-detection of the Swift/UVOT source
  26. LIGO/Virgo S190425z: VISTA K-band observations of the Swift/UVOT Transient
  27. LIGO/Virgo S190425z: MASTER explanation of the nature of an optical flash detected by a Swift as a short flare on a fast-moving WISE brown
  28. LIGO/Virgo S190425z: No i-band detection of the Swift/UVOT transient in SkyMapper observations
  29. LIGO/Virgo S190425z: 1.5m OSN and 10.4m imaging of the UVOT source field
  30. LIGO/Virgo S190425z: No source found at UVOT source location at 6 hrs after LVC report
  31. LIGO/Virgo S190426c: DG19ytre and DG19kplb 1.5m OSN imaging and 10.4m GTC spectroscopy
  32. LIGO/Virgo S190425z: No Optical Detection of the Swift/UVOT Transient in ASAS-SN observations hours before and after discovery
  33. LIGO/Virgo S190425z: No Optical Detection of the Swift/UVOT Transient with Las Cumbres Observatory
  34. LIGO/Virgo S190425z: Pre-discovery NIR limits of the UVOT transient candidate from Gattini-IR
  35. LIGO/Virgo S190425z: ZTF photometry of the UVOT transient candidate hours before discovery
  36. LIGO/Virgo S190426c: J-GEM optical/NIR follow-up observations
  37. GRB 190419A: AstroSat CZTI detection
  38. GRB 190427A: Fermi GBM detection
  39. LIGO/Virgo S190426c: Optical Wide-field Search with the Zwicky Transient Facility
  40. LIGO/Virgo S190426c: Insight-HXMT/HE observation
  41. GRB 190427A: BOOTES-1 and BOOTES-5/JGT early follow-up observations
  42. LIGO/Virgo S190425z: BOOTES-5/JGT observations of galaxies
  43. LIGO/Virgo S190425z - ePESSTO+ spectrum of candidate PS19qu
  44. GRB 190427A: Swift detection of a short burst
  45. LIGO/Virgo S190426c: a possible lensed NS-NS merger
  46. LIGO/Virgo S190426c: Fermi GBM Observations
  47. LIGO/Virgo S190426c: HAWC follow-up
  48. LIGO/Virgo S190425z: Keck NIR spectroscopy shows AT2019ebq is a supernova
  49. LIGO/Virgo S190425z: Nearby Galaxies in the Updated Localization Volume
  50. LIGO/Virgo S190425z: GROND observations of AT2019ebq/PS19qp
  51. LIGO/Virgo S190425z: AMI-LA radio observations of two ZTF afterglow candidates.
  52. LIGO/Virgo S190425z: LWA1 observations
  53. LIGO/Virgo S190425z: Insight-HXMT/HE observation
  54. LIGO/Virgo S190425z: Liverpool Telescope spectroscopy of ZTF19aarykkb
  55. LIGO/Virgo S190425z - HCT spectroscopy
  56. LIGO/Virgo S190425z: KPED Follow-Up Observations
  57. LIGO/Virgo S190425z: CLU/NED Galaxies in the Localization Volume
  58. LIGO/Virgo S190425z: Candidates from the Zwicky Transient Facility
  59. LIGO/Virgo S190425z: Fermi GBM Observations
  60. LIGO/Virgo S190425z: further analysis of INTEGRAL data
  61. LIGO/VirgoS190425z: HAWC follow-up
  62. LIGO-Virgo S190421ar:Insight-HXMT/HE observation
  63. GRB 190424A: Swift detection of a burst
  64. GRB 190422A: Fermi GBM detection
  65. GRB 190422A: Swift detection of a burst
  66. LIGO/Virgo S190421ar: Fermi-GBM Observations
  67. LIGO/Virgo S190421ar: HAWC follow-up
  68. Konus-Wind observation of GRB 190415A
  69. Fermi trigger 576241792 / GRB 190406B: MASTER optical observation
  70. GRB 190406B: Zwicky Transient Facility Follow-Up of a Fermi Short GRB (Trigger 576241792)
  71. GRB 190326A: Swift XRT and UVOT follow-up observations
  72. IPN Triangulation of GRB 190415A
  73. GRB 190415A: Insight-HXMT/HE detection
  74. GRB 190407B: AstroSat CZTI detection
  75. GRB 190411A: AstroSat CZTI detection
  76. GRB 190411A: Insight-HXMT/HE detection
  77. LIGO/Virgo S190412m: Fermi-GBM Observations
  78. LIGO/Virgo S190412m: Insight-HXMT/HE observation
  79. LIGO/Virgo S190412m: HAWC follow-up
  80. IceCube-190331A: Swift-XRT Follow-up Observations
  81. LIGO/Virgo S190408an: TMTS Optical Observation
  82. LIGO/Virgo S190408an: MASTER 3 OT's more detection
  83. Konus-Wind observation of GRB 190404B
  84. GRB 190409A: Swift detection of a possible burst
  85. LIGO/Virgo S190408an: Insight-HXMT/HE observation
  86. LIGO/Virgo S190408an: MASTER OT detection
  87. CORRECTED TARGET NAME: GRB 190408A: MAXI/GSC detection
  88. GRB 140408A: MAXI/GSC detection
  89. LIGO-Virgo S190408an: HAWC follow-up
  90. GRB 190404C: Swift-XRT afterglow detection
  91. Hard Fermi GRB190404.29/TriggNum576054086: MASTER optical counterpart discovery near PGC020455
  92. GRB 190404B: CALET Gamma-Ray Burst Monitor detection
  93. GRB 190331C: AstroSat CZTI detection
  94. GRB 140404C: MAXI/GSC detection
  95. GRB 140404B: MAXI/GSC detection
  96. Trigger 896552: Swift detection of PSR B1055-52
  97. Konus-Wind observation of GRB 190329A
  98. GRB 190331B: BOOTES-3/YA optical observations
  99. GRB 190326B: AstroSat CZTI detection
  100. GRB 190401A: Insight-HXMT/HE detection

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