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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"

3039 results found.

  1. Fermi trigger No 642991619: Global MASTER-Net observations report
  2. Fermi GRB 210516A: Global MASTER-Net observations report
  3. GRB 210515C: Swift-XRT refined Analysis
  4. GRB 210515C: Swift detection of a burst
  5. Fermi GRB 210515B: Global MASTER-Net observations report
  6. Fermi GRB 210515A: Global MASTER-Net observations report
  7. Fermi trigger No 642538568: Global MASTER-Net observations report
  8. IPN triangulation of GRB 210427A
  9. Fermi GRB 210511A: Global MASTER-Net observations report
  10. GRB 210511A: Fermi GBM Final Real-time Localization
  11. Fermi GRB 210510A: Global MASTER-Net observations report
  12. GRB 210509A: Swift-BAT refined analysis
  13. Fermi GRB 210507A: Global MASTER-Net observations report
  14. ZTF21aayokph (AT2021lfa): Mondy and Koshka observatory optical observations
  15. Lowell Discovery Telescope Observations of ZTF21aayokph (AT2021lfa)
  16. ZTF21aayokph (AT2021lfa): Assy optical observations
  17. Fermi GRB 210501A: Global MASTER-Net observations report
  18. Fermi trigger No 641601187: Global MASTER-Net observations report
  19. GRB 210427A: GECAM detection
  20. GRB 210427A: BALROG localization (Fermi Trigger / GRB 210427206)
  21. GRB 210427A: Fermi GBM Final Real-time Localization
  22. GRB 210420B: Assy optical observations
  23. GRB 210421A: Swift-BAT refined analysis
  24. GRB 210420B: Swift-XRT refined Analysis
  25. GRB 210420B: DDOTI Detection of the Afterglow
  26. GRB 210420B: Multiband photometry from NOT
  27. GRB 210420B: Optical observations
  28. GRB 210419A: LCO Optical Upper Limit
  29. IceCube Alert 210416.09: Global MASTER-Net observations report
  30. GRB 210413B: Swift/BAT detection and probable localization of a short burst
  31. GRB 210410A: AstroSat CZTI detection
  32. Fermi GRB 210415A: Global MASTER-Net observations report
  33. GRB 210411C: Swift-BAT refined analysis
  34. Fermi GRB 210411A: Global MASTER-Net observations report
  35. Integral GRB210406.72: Global MASTER-Net observations report
  36. GRB 210402A: Swift-BAT refined analysis
  37. Fermi trigger No 639199407: Global MASTER-Net observations report
  38. GRB 210403A: Swift-BAT refined analysis
  39. Fermi GRB 210324B: Global MASTER-Net observations report
  40. GRB210318B: Swift detection of a burst
  41. GRB 210312B: Redshift from OSIRIS/GTC
  42. GRB 210312B: GTC photometry
  43. Fermi GRB 210312A: Global MASTER-Net observations report
  44. GRB 210308A: Swift-BAT refined analysis
  45. GRB 210307A: Swift-BAT refined analysis
  46. GRB 210306A: Swift-BAT refined analysis
  47. GRB 210305A: Swift-BAT refined analysis
  48. GRB 210307A: Swift detection of a burst
  49. GRB 210306A: iTelescope T24 optical observations
  50. GRB 210306A: Swift detection of a burst with a bright optical counterpart
  51. GRB 210226A: Swift detection of a burst
  52. Fermi trigger No 635922820: Global MASTER-Net observations report
  53. Konus-Wind detection of GRB 210222A
  54. GRB 210222A: CALET Gamma-Ray Burst Monitor detection
  55. GRB 210218A: Swift-BAT refined analysis
  56. GRB 210204A (ZTF21aagwbjr/AT2021buv): continued Assy and Mondy optical observations
  57. GRB 210212B (TF21aakruew/AT2021cwd): Assy optical observations
  58. IPN triangulation of GRB 210212B (consistent with ZTF21aakruew/AT2021cwd)
  59. GRB 210211A: Swift/UVOT Detection
  60. GRB 210211A: REM optical/NIR afterglow detection
  61. GRB 210211A: Swift detection of a burst
  62. GRB 210210A: Swift-BAT refined analysis
  63. Fermi GRB 210210B: Global MASTER-Net observations report
  64. Swift GRB 210210A: Global MASTER-Net observations report
  65. GRB 210207B: AstroSat CZTI detection
  66. GRB 210204A: AstroSat CZTI Detection
  67. IPN triangulation of GRB 210204A
  68. GRB 210204: Fermi GBM observation
  69. Fermi trigger No 633879387: Global MASTER-Net observations report
  70. GRB 210120A(MASTER OT J105242.66+152355.0 / AT2021axc): Mondy optical observations
  71. Short Fermi GRB 210119A or new SGR Swift J1851.2-6148: Possible MASTER Short OT detection
  72. Fermi GRB 210119A: Global MASTER-Net observations report
  73. GRB 201227A: continued Chilescope confirmation of variability of possible optical counterpart, redshift estimating
  74. Fermi trigger No 631602681: Global MASTER-Net observations report
  75. GRB 210104A: iTelescope optical upper limit
  76. GRB 210104B: Swift-BAT refined analysis
  77. INTEGRAL Weak #8913: AROMA-N Optical Observation
  78. Fermi trigger No 631118376: Global MASTER-Net observations report
  79. Fermi trigger No 631104264: Global MASTER-Net observations report
  80. GRB 201104B: Maidanak and CrAO optical observations
  81. GRB 201223A: Mondy and Kitab optical observations
  82. Fermi trigger No 630389391: Global MASTER-Net observations report
  83. GRB 201221D: LCOGT upper limits
  84. Fermi GRB 201218A: Global MASTER-Net observations report
  85. GRB 201216C: MAGIC detection in very high energy gamma rays
  86. Fermi GRB 201216A: Global MASTER-Net observations report
  87. Fermi GRB 201214B: Global MASTER-Net observations report
  88. IceCube Alert 201209.43: Global MASTER-Net observations report
  89. IceCube-201130A: Optical and NIR Imaging Follow-up by Kanata Telescope
  90. Swift GRB201209.24: Global MASTER-Net observations report
  91. GRB 201203A: DDOTI Observations
  92. IceCube Alert 201130.85: Global MASTER-Net observations report
  93. Baksan Neutrino Observatory Alert 201128.90: Global MASTER-Net observations report
  94. Fermi trigger No 628140709: Global MASTER-Net observations report
  95. AMON IC_HAWC NuEm-201124A: No Neutrino Counterpart detected with ANTARES
  96. INTEGRAL Weak #8831 and #8832: AROMA-N Optical Observation
  97. GRB 201116A: OSN Afterglow Candidate
  98. Fermi trigger No 627198169: Global MASTER-Net observations report
  99. ZTF20acozryr/AT2020yxz (GRB 201103B): Mondy, Kitab, TSHAO optical observations
  100. Fermi trigger No 626247072: Global MASTER-Net observations report

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