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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"

4258 results found.

  1. LIGO/Virgo S190425z: DECam Observations of the UVOT Candidate Region
  2. LIGO/Virgo S190426c: OAJ-GRANDMA observation report
  3. LIGO/Virgo S190425z: No source found at UVOT source location at 6 hrs after LVC report
  4. LIGO/Virgo S190425z: SVOM/GWAC-F60A observations
  5. LIGO/Virgo S190426c: DDOTI/OAN Optical Observations
  6. LIGO/Virgo S190426c: RATIR Optical and NIR Observations of Galaxies
  7. LIGO/Virgo S190426c: COATLI Optical Observations of Galaxies
  8. LIGO/Virgo S190425z: Transient found in Swift/UVOT counterpart search
  9. LIGO/Virgo S190425z: Further confirmation for the classification of PS19qp/AT 2019ebq as a supernova
  10. Fermi GRB190427.19 Global MASTER-Net observations report
  11. LIGO/Virgo S190426c: MMT Follow-Up Observations
  12. LIGO/Virgo S190426c: Lick/KAIT Follow-Up Observations
  13. LIGO/Virgo S190426c: CNEOST Optical Observations
  14. LIGO/Virgo S190425z: CNEOST Optical Observations
  15. LIGO/Virgo S190425z: BOOTES-5/JGT observations of galaxies
  16. LIGO/Virgo S190425z: Additional Pan-STARRS transients in the skymap
  17. LIGO/Virgo S190425z: GRANDMA follow-up observations with Les Makes-T60, AZT-8 and Abastumani-T70
  18. LIGO/Virgo S190426c: SAO optical observation
  19. LIGO/Virgo S190425z: Further MMT Follow-Up Observations
  20. LIGO/Virgo S190426c: INTEGRAL prompt observation
  21. Baksan Neutrino Observatory Alert 190405.62: Global MASTER-Net:LIGO/Virgo S190425z: PanSTARR OT AT2019ebq/PS19qp
  22. LIGO/Virgo S190425z: COATLI Observations of Galaxies
  23. LIGO/Virgo S190425z: TAROT-GRANDMA observation report
  24. LIGO/Virgo S190425z: KMTNet Observation
  25. LIGO/Virgo S190425z: Pan-STARRS observations and transients in the skymap
  26. LIGO/Virgo S190425z: ZTF19aarykkb Imaging from Las Cumbres Observatory
  27. LIGO/Virgo S190425z - GROWTH-India follow-up of two ZTF candidates
  28. LIGO/Virgo S190425z: ATLAS observations of the S190425z skymap
  29. LIGO/Virgo S190425z: J-GEM optical follow-up observations with Subaru/FOCAS
  30. LIGO/Virgo S190425z: Xinglong/Schmidt follow-up observations
  31. LIGO/Virgo S190425z: Lick/KAIT Follow-Up Observations
  32. LIGO/Virgo S190425z: further analysis of INTEGRAL data
  33. Fermi GRB190425.09 Global MASTER-Net observations report
  34. LIGO/Virgo S190421ar: Lick/KAIT Follow-Up Observations
  35. GRB 190422A: Swift detection of a burst
  36. LIGO/Virgo S190421ar: Fermi-GBM Observations
  37. LIGO/Virgo S190421ar Global MASTER-Net observations report
  38. Fermi GRB190419.41 Global MASTER-Net observations report
  39. Fermi trigger 576241792 / GRB 190406B: MASTER optical observation
  40. GRB 190326A: Swift XRT and UVOT follow-up observations
  41. LIGO/Virgo S190412m: TAROT-GRANDMA observation report.
  42. CORRECTED TARGET NAME: GRB 190408A: MAXI/GSC detection
  43. GRB 140408A: MAXI/GSC detection
  44. GRB 140404B: MAXI/GSC detection
  45. GRB 190330A: MITSuME Akeno and Okayama optical upper limits
  46. Trigger 896552: Swift detection of PSR B1055-52
  47. GRB 190331B: Swift observations of a ground-detected burst
  48. GRB 190329A: CALET Gamma-Ray Burst Monitor detection
  49. GRB 190326A: Swift-BAT refined analysis - a soft-short GRB or an SGR
  50. GRB 190320A: Swift-BAT refined analysis
  51. GRB 190311A: Swift-BAT refined analysis
  52. GRB190219A: MASTER Global Robotic Net optical observation
  53. GRB 180703A: VLT/MUSE host galaxy redshift measurement
  54. Konus-Wind observation of GRB 190206A
  55. IPN Triangulation of GRB 190206A (short/extremely bright)
  56. Konus-Wind observation of GRB 190203A
  57. GRB 190202A: R and I band observation from HCT
  58. GRB 190129B: MASTER Global Robotic Net optical observation
  59. GRB 190129A: CALET Gamma-Ray Burst Monitor detection
  60. GRB 190129A: Fermi GBM detection
  61. GRB 190129A: MAXI/GSC detection
  62. Swift Trigger 886157: MASTER optical observation
  63. Swift Trigger 886157: Swift detection of a new transient Swift J1728.9-3613
  64. GRB 190123A: Swift detection of a burst
  65. IPN Triangulation of GRB 190118A (long)
  66. GRB 190114C: OASDG optical observations
  67. GRB 190114C: NOT optical counterpart and redshift
  68. GRB 190114C: Swift detection of a very bright burst with a bright optical counterpart
  69. IceCube-190104A: AstroSat CZTI counterpart search
  70. FRB 181228: Global MASTER Net optical inspection
  71. GRB 181222B: Global MASTER Net observations of short bright Fermi GRB
  72. GRB 181222B: Global MASTER Net observations of the short bright Fermi GRB error box.
  73. Swift Trigger 878504 is not astrophysical
  74. GRB 181222A: MAXI/GSC detection
  75. GRB 181213A: Swift/UVOT Observations
  76. GRB 181213A: Mondy optical observations
  77. GRB 181213A: continued TSHAO optical observations
  78. GRB 181213A: Enhanced Swift-XRT position
  79. IPN Triangulation of GRB 181212A (long)
  80. GRB181213A: Swift/UVOT Detection
  81. GRB 181213A: Swift-XRT observations
  82. GRB 181213A: BOOTES-5/JGT optical observations
  83. GRB 181126A: Prompt enhanced Swift-XRT position
  84. IPN Triangulation of GRB 181121A (short)
  85. Fermi GRB 181105.31: Global MASTER Net optical observations
  86. GRB 181103A: MITSuME Okayama optical upper limits
  87. GRB 181030A: MASTER Net OT detection
  88. GRB 181030A: Swift detection of a burst with a possible optical counterpart
  89. IPN Triangulation of GRB 181028A (long)
  90. GRB 180728B: Zwicky Transient Facility Follow-Up of a Fermi Short GRB (Trigger 554505003)
  91. GRB 181022A: Swift-XRT refined Analysis
  92. GRB 181022A: MITSuME Akeno optical upper limits
  93. GRB 181013A: Swift detection of a probable burst
  94. GRB 181010A: MASTER-Argentina OT detection
  95. GRB 180923A: MASTER inspection MAXI/GSC error box
  96. GRB 180923A: MAXI/GSC detection
  97. Konus-Wind of the very bright GRB 180914B
  98. GRB 180914A: MASTER automatic inspection
  99. GRB 180905A, Swift-BAT refined analysis
  100. GRB 180905A: MITSuME Akeno optical upper limits

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