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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"

3850 results found.

  1. LIGO/Virgo S190425z: Further confirmation for the classification of PS19qp/AT 2019ebq as a supernova
  2. Fermi GRB190427.19 Global MASTER-Net observations report
  3. LIGO/Virgo S190426c: MMT Follow-Up Observations
  4. LIGO/Virgo S190426c: Lick/KAIT Follow-Up Observations
  5. LIGO/Virgo S190426c: CNEOST Optical Observations
  6. LIGO/Virgo S190425z: CNEOST Optical Observations
  7. LIGO/Virgo S190425z: BOOTES-5/JGT observations of galaxies
  8. LIGO/Virgo S190425z: Additional Pan-STARRS transients in the skymap
  9. LIGO/Virgo S190425z: GRANDMA follow-up observations with Les Makes-T60, AZT-8 and Abastumani-T70
  10. LIGO/Virgo S190426c: SAO optical observation
  11. LIGO/Virgo S190425z: Further MMT Follow-Up Observations
  12. LIGO/Virgo S190426c: INTEGRAL prompt observation
  13. Baksan Neutrino Observatory Alert 190405.62: Global MASTER-Net:LIGO/Virgo S190425z: PanSTARR OT AT2019ebq/PS19qp
  14. LIGO/Virgo S190425z: COATLI Observations of Galaxies
  15. LIGO/Virgo S190425z: TAROT-GRANDMA observation report
  16. LIGO/Virgo S190425z: KMTNet Observation
  17. LIGO/Virgo S190425z: Pan-STARRS observations and transients in the skymap
  18. LIGO/Virgo S190425z: ZTF19aarykkb Imaging from Las Cumbres Observatory
  19. LIGO/Virgo S190425z - GROWTH-India follow-up of two ZTF candidates
  20. LIGO/Virgo S190425z: ATLAS observations of the S190425z skymap
  21. LIGO/Virgo S190425z: J-GEM optical follow-up observations with Subaru/FOCAS
  22. LIGO/Virgo S190425z: Xinglong/Schmidt follow-up observations
  23. LIGO/Virgo S190425z: Lick/KAIT Follow-Up Observations
  24. LIGO/Virgo S190425z: further analysis of INTEGRAL data
  25. Fermi GRB190425.09 Global MASTER-Net observations report
  26. LIGO/Virgo S190421ar: Lick/KAIT Follow-Up Observations
  27. GRB 190422A: Swift detection of a burst
  28. LIGO/Virgo S190421ar: Fermi-GBM Observations
  29. LIGO/Virgo S190421ar Global MASTER-Net observations report
  30. Fermi GRB190419.41 Global MASTER-Net observations report
  31. Fermi trigger 576241792 / GRB 190406B: MASTER optical observation
  32. GRB 190326A: Swift XRT and UVOT follow-up observations
  33. LIGO/Virgo S190412m: TAROT-GRANDMA observation report.
  34. CORRECTED TARGET NAME: GRB 190408A: MAXI/GSC detection
  35. GRB 140408A: MAXI/GSC detection
  36. GRB 140404B: MAXI/GSC detection
  37. GRB 190330A: MITSuME Akeno and Okayama optical upper limits
  38. Trigger 896552: Swift detection of PSR B1055-52
  39. GRB 190331B: Swift observations of a ground-detected burst
  40. GRB 190329A: CALET Gamma-Ray Burst Monitor detection
  41. GRB 190326A: Swift-BAT refined analysis - a soft-short GRB or an SGR
  42. GRB 190320A: Swift-BAT refined analysis
  43. GRB 190311A: Swift-BAT refined analysis
  44. GRB190219A: MASTER Global Robotic Net optical observation
  45. GRB 180703A: VLT/MUSE host galaxy redshift measurement
  46. Konus-Wind observation of GRB 190206A
  47. IPN Triangulation of GRB 190206A (short/extremely bright)
  48. Konus-Wind observation of GRB 190203A
  49. GRB 190202A: R and I band observation from HCT
  50. GRB 190129B: MASTER Global Robotic Net optical observation
  51. GRB 190129A: CALET Gamma-Ray Burst Monitor detection
  52. GRB 190129A: Fermi GBM detection
  53. GRB 190129A: MAXI/GSC detection
  54. Swift Trigger 886157: MASTER optical observation
  55. Swift Trigger 886157: Swift detection of a new transient Swift J1728.9-3613
  56. GRB 190123A: Swift detection of a burst
  57. IPN Triangulation of GRB 190118A (long)
  58. GRB 190114C: OASDG optical observations
  59. GRB 190114C: NOT optical counterpart and redshift
  60. GRB 190114C: Swift detection of a very bright burst with a bright optical counterpart
  61. IceCube-190104A: AstroSat CZTI counterpart search
  62. FRB 181228: Global MASTER Net optical inspection
  63. GRB 181222B: Global MASTER Net observations of short bright Fermi GRB
  64. GRB 181222B: Global MASTER Net observations of the short bright Fermi GRB error box.
  65. Swift Trigger 878504 is not astrophysical
  66. GRB 181222A: MAXI/GSC detection
  67. GRB 181213A: Swift/UVOT Observations
  68. GRB 181213A: Mondy optical observations
  69. GRB 181213A: continued TSHAO optical observations
  70. GRB 181213A: Enhanced Swift-XRT position
  71. IPN Triangulation of GRB 181212A (long)
  72. GRB181213A: Swift/UVOT Detection
  73. GRB 181213A: Swift-XRT observations
  74. GRB 181213A: BOOTES-5/JGT optical observations
  75. GRB 181126A: Prompt enhanced Swift-XRT position
  76. IPN Triangulation of GRB 181121A (short)
  77. Fermi GRB 181105.31: Global MASTER Net optical observations
  78. GRB 181103A: MITSuME Okayama optical upper limits
  79. GRB 181030A: MASTER Net OT detection
  80. GRB 181030A: Swift detection of a burst with a possible optical counterpart
  81. IPN Triangulation of GRB 181028A (long)
  82. GRB 180728B: Zwicky Transient Facility Follow-Up of a Fermi Short GRB (Trigger 554505003)
  83. GRB 181022A: Swift-XRT refined Analysis
  84. GRB 181022A: MITSuME Akeno optical upper limits
  85. GRB 181013A: Swift detection of a probable burst
  86. GRB 181010A: MASTER-Argentina OT detection
  87. GRB 180923A: MASTER inspection MAXI/GSC error box
  88. GRB 180923A: MAXI/GSC detection
  89. Konus-Wind of the very bright GRB 180914B
  90. GRB 180914A: MASTER automatic inspection
  91. GRB 180905A, Swift-BAT refined analysis
  92. GRB 180905A: MITSuME Akeno optical upper limits
  93. GRB 180828A: Swift detection of a GRB or possible Galactic Transient Swift J1754.9-2548
  94. GRB 180824A: MASTER inspection IPN short GRB error box
  95. GRB 180809B: AstroSat CZTI detection
  96. GRB 180728A: MASTER early polarization and 19 days monitoring
  97. MASTER: OT detection during two Fermi GBM triggers (555263883 and 555263883) error boxes inspection in 22.5 mag SDSS galaxy direction
  98. GRB180809B: MASTER Triple Independent Automatic OT Detection
  99. GRB 180809B: LCO Sutherland observations
  100. GRB 180809B: GROND Detection of the NIR Afterglow

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