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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"

16320 results found.

  1. GRB 180914B: DDOTI/OAN Detection and Confirmation of Fading
  2. GRB 180914B: GOTO optical detection
  3. GRB 180914B : continued TSHAO optical observations
  4. GRB 180914B: VLT/X-shooter spectroscopic redshift
  5. GRB 180914B: MASTER OT automatic dtection
  6. GRB 180914B : TSHAO optical observations
  7. GRB 180914B: Continued RATIR Optical and NIR Observations
  8. GRB180914B: Swift UVOT detection of an optical afterglow
  9. GRB 180914B: Optical counterpart observation from OAJ
  10. GRB 180914B: RATIR Optical and NIR Observations
  11. GRB 180914B: KAIT Optical Afterglow Candidate
  12. GRB 180914A: RATIR Optical and NIR Observations
  13. GRB 180914A: MASTER automatic inspection
  14. GRB 180905A: Swift/UVOT Upper Limits
  15. GRB 180905A: RATIR Optical and NIR Observations
  16. GRB 180905A: MITSuME Akeno optical upper limits
  17. GRB 180904A: BOOTES-2/TELMA early observations
  18. GRB 180905A: BOOTES-3/YA optical observations
  19. GRB 180904A: AbAO optical upper limit
  20. GRB 180904A: Swift/UVOT Upper Limits
  21. GRB 180904A: RATIR Optical and NIR Observations
  22. GRB 180904A: SAO RAS optical observations
  23. GRB 180904A: NOT optical observations, candidate host galaxy
  24. GRB 180828A: Swift/UVOT Upper Limits
  25. GRB 180828A: RATIR Optical and NIR Observations
  26. GRB 180818B: TSHAO optical upper limit
  27. GRB 180823A: Swift/UVOT Upper Limits
  28. GRB 180823A: RATIR Optical and NIR Observations
  29. GRB 180821A: Swift/UVOT Upper Limits
  30. GRB 180821A: iTelescope counterpart is not the afterglow
  31. GRB 180818B: 1.5m OSN optical afterglow candidate
  32. GRB 180821A: iTelescope optical afterglow detection
  33. GRB 180821A: BOOTES-3/YA optical observations
  34. GRB 180818B: Swift/UVOT Upper Limits
  35. GRB 180818A: Swift/UVOT Upper Limits
  36. GRB 180728A: MASTER early polarization and 19 days monitoring
  37. GRB 180728A: discovery of the associated supernova
  38. LIGO/Virgo GW170817: A steep decline in the radio light curve and prediction for the X-rays
  39. GRB 180812A: COATLI Detection and Light Curve
  40. GRB 180812A: BOOTES-5/JGT optical afterglow detection
  41. MASTER: OT detection during two Fermi GBM triggers (555263883 and 555263883) error boxes inspection in 22.5 mag SDSS galaxy direction
  42. GRB 180809B: CrAO optical observations
  43. GRB 180809B, Swift-BAT refined analysis
  44. Swift Trigger 852625: Swift/BAT/XRT/UVOT observations
  45. GRB 180809B: VLT optical upper limits
  46. GRB180809B: MASTER Triple Independent Automatic OT Detection
  47. GRB 180809B: LCO Sutherland observations
  48. GRB 180809B: GROND Detection of the NIR Afterglow
  49. GRB 180809B: RATIR Optical Observations and Confirmation of Rapid Fading
  50. GRB180809B: MASTER OT observation
  51. GRB 180805B: Teide LCO optical observations
  52. GRB 180809A: iTelescope optical limit
  53. GRB 180809B: Swift detection of a burst with an optical afterglow
  54. GRB 180806A: NOT optical observations
  55. GRB 180806A/180806.98: RATIR Optical Observations of MASTER OT J004613.05+242014.1
  56. GRB 180805B: ESO/NTT optical observations
  57. GRB 180805B: COATLI Optical Observations
  58. GRB 180805B: 1.5m OSN I-band observation
  59. GRB 180805B: GOTO optical limits
  60. GRB 180805B: VLT optical and near-infrared observations
  61. GRB 180805B: MASTER optical late inspection short GRB with extended emission
  62. GRB 180805B: Swift/UVOT Upper Limits
  63. GMRT radio detection of GRB 180720B
  64. Fermi Trigger 554765006: MASTER optical inspection
  65. FRB 180725A: MASTER optical observations of the Fast Radio Burst error box
  66. GRB 180728B: GOTO optical search over IPN region
  67. GRB 180728A: No evidence of SN in early VLT/X-shooter spectra
  68. GRB 180728A: A long GRB of the X-ray flash (XRF) subclass, expecting supernova appearance
  69. GRB 180728B: MASTER optical observations short GRB IPN error box
  70. GRB 180727A: Swift/UVOT Upper Limits
  71. GRB 180728A: VLT/X-shooter redshift of a nearby energetic GRB
  72. GRB 180728A: MASTER OT J165415.75-540239.27 is the Optical Counterpart of GRB
  73. GRB 180728A: MASTER OT (= new object) detection
  74. GRB 180720B: OAJ optical observations
  75. GRB 180720B long follow up requested
  76. GRB 180721A: KAIT Optical Upper Limit
  77. GRB 180720B: KAIT Optical Observations
  78. GRB 180718B: Swift-XRT observations
  79. GRB 180723.13: MASTER optical observation of the short Fermi GBM trigger number 554008254
  80. GRB 180723.76: MASTER optical observation of the bright long Fermi GBM trigger number 554062193
  81. GRB 180720B: D50 optical observations
  82. GRB 180720B: MASTER Global Net OT observations
  83. GRB 180721A: MITSuME Akeno optical upper limits
  84. GRB 180720B: REM photometry
  85. GRB 180720B: ISON-Castelgrande optical observations
  86. GRB 180720B: Testing the universality of the newly born neutron star in BdHNe
  87. GRB 180721A: BOOTES-5/JGT optical observations
  88. GRB 180720B: COATLI Optical Detection
  89. GRB 180720C: BOOTES-2/TELMA optical observations
  90. GRB 180721A: Swift/UVOT Upper Limits
  91. FRB 180714: MASTER optical inspection of the Fast Rado Burst Transient
  92. GRB 180720C: MASTER optical observation
  93. ANTARES neutrino Alert180713.02: MASTER optical observation
  94. Fermi Trigger 553879512: MASTER optical observation
  95. GRB 180722A: MASTER optical observation
  96. GRB 180720B: MITSuME Ishigaki optical observations
  97. GRB 180720B: VLT/X-shooter redshift
  98. GRB 180720C: Swift/UVOT Upper Limits
  99. GRB 180720B: LCO optical afterglow observations
  100. GRB 180720B: OSN detection, fading slower?

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