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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"

21092 results found.

  1. GRB 180904A: BOOTES-2/TELMA early observations
  2. GRB 180905A: BOOTES-3/YA optical observations
  3. GRB 180904A: Swift/UVOT Upper Limits
  4. GRB 180904A: RATIR Optical and NIR Observations
  5. GRB 180904A: LT early observations
  6. GRB 180904A: SAO RAS optical observations
  7. GRB 180904A: OSN observations
  8. GRB 180904A: NOT optical observations, candidate host galaxy
  9. GRB 180829A: Swift-XRT observations
  10. GRB 180828A: Swift/UVOT Upper Limits
  11. GRB 180828A: RATIR Optical and NIR Observations
  12. GRB 180829A: Tiled Swift observations
  13. GRB 180728A: classification of the associated SN 2018fip
  14. GRB 180824A: MASTER inspection IPN short GRB error box
  15. GRB 180823A: Swift/UVOT Upper Limits
  16. GRB 180823A: RATIR Optical and NIR Observations
  17. GRB 180821A: VLT observations
  18. GRB 180821A: Swift/UVOT Upper Limits
  19. GRB 180821A: LCO Siding Springs observations
  20. GRB 180818B: 1.5m OSN optical afterglow candidate
  21. GRB 180821A: iTelescope optical afterglow detection
  22. GRB 180821A: BOOTES-3/YA optical observations
  23. GRB180806A: confirmation of the X-ray afterglow
  24. GRB 180818B: Fermi GBM observations
  25. GRB 180818B: Swift/UVOT Upper Limits
  26. GRB 180818A: Swift/UVOT Upper Limits
  27. GRB 180728A: MASTER early polarization and 19 days monitoring
  28. GRB 180728A: discovery of the associated supernova
  29. GRB 180809A: further Swift/XRT observations
  30. Correction: Chandra X-ray observations of GW170817 at 1 year post-merger: increasingly rapid fading
  31. LIGO/Virgo GW170817: A steep decline in the radio light curve and prediction for the X-rays
  32. GRB 180812A: Swift/UVOT Detection
  33. Chandra X-ray observations of GW170817 at 1 year post-merger: increasingly rapid fading
  34. GRB 180809B: ePESSTO NTT NIR observations
  35. GRB 180812A: COATLI Detection and Light Curve
  36. GRB 180812A: BOOTES-5/JGT optical afterglow detection
  37. GRB180809B TUG T60 observations
  38. MASTER: OT detection during two Fermi GBM triggers (555263883 and 555263883) error boxes inspection in 22.5 mag SDSS galaxy direction
  39. GRB 180809B: CrAO optical observations
  40. GRB 180809B, Swift-BAT refined analysis
  41. Swift Trigger 852625: Swift/BAT/XRT/UVOT observations
  42. GRB 180809B: Swift/UVOT Detection
  43. GRB180809B: MASTER Triple Independent Automatic OT Detection
  44. GRB 180809B: LCO Sutherland observations
  45. GRB 180809B: GROND Detection of the NIR Afterglow
  46. GRB 180809B: RATIR Optical Observations and Confirmation of Rapid Fading
  47. GRB 180805B: Teide LCO optical observations
  48. GRB 180809A: Swift-XRT afterglow detection
  49. GRB 180809A: Tiled Swift observations
  50. GRB 180806A: NOT optical observations
  51. GRB 180806A: Swift-XRT afterglow detection
  52. GRB 180806A/180806.98: RATIR Optical Observations of MASTER OT J004613.05+242014.1
  53. GRB 180806A: Swift ToO observations
  54. GRB 180806.94: COATLI Detection of MASTER OT J004613.05+242014.1 and Confirmation of Fading
  55. GRB 180806.94: MASTER possible OT detection in Fermi GMB trigger 555287944 error box
  56. GRB 180805B: ESO/NTT optical observations
  57. GRB 180805B: COATLI Optical Observations
  58. GRB 180805B: GOTO optical limits
  59. GRB 180805B: VLT optical and near-infrared observations
  60. GRB 180805B: Swift/UVOT Upper Limits
  61. GMRT radio detection of GRB 180720B
  62. Fermi Trigger 554765006: MASTER optical inspection
  63. FRB 180725A: MASTER optical observations of the Fast Radio Burst error box
  64. GRB 180728B: GOTO optical search over IPN region
  65. GRB 180728A: No evidence of SN in early VLT/X-shooter spectra
  66. GRB 180728A: A long GRB of the X-ray flash (XRF) subclass, expecting supernova appearance
  67. GRB 180728B: MASTER optical observations short GRB IPN error box
  68. GRB 180728A: Swift/UVOT Detection
  69. GRB 180727A: Swift/UVOT Upper Limits
  70. GRB 180728A: Swift-XRT observations
  71. GRB 180728A: MASTER OT (= new object) detection
  72. NuSTAR observations of GRB 180720B
  73. GRB 180720B: OAJ optical observations
  74. GRB 180720B: AMI-LA 15.5 GHz observation
  75. GRB 180721A: KAIT Optical Upper Limit
  76. GRB 180720B: KAIT Optical Observations
  77. GRB 180722A: Swift-XRT observations
  78. GRB 180718B: Swift-XRT observations
  79. GRB 180718A: Swift-XRT observations
  80. GRB 180723.13: MASTER optical observation of the short Fermi GBM trigger number 554008254
  81. GRB 180722A: MASTER second inspection
  82. GRB 180723.76: MASTER optical observation of the bright long Fermi GBM trigger number 554062193
  83. GRB 180720B: D50 optical observations
  84. GRB 180720B: MASTER Global Net OT observations
  85. GRB 180720B: REM photometry
  86. GRB 180720B: ISON-Castelgrande optical observations
  87. GRB 180720B: Testing the universality of the newly born neutron star in BdHNe
  88. GRB 180721A: BOOTES-5/JGT optical observations
  89. GRB 180720C: BOOTES-2/TELMA optical observations
  90. GRB 180722A: Tiled Swift observations
  91. GRB 180721A: Swift/UVOT Upper Limits
  92. FRB 180714: MASTER optical inspection of the Fast Rado Burst Transient
  93. GRB 180720C: MASTER optical observation
  94. ANTARES neutrino Alert180713.02: MASTER optical observation
  95. Fermi Trigger 553879512: MASTER optical observation
  96. GRB 180722A: MASTER optical observation
  97. GRB 180720B: MITSuME Ishigaki optical observations
  98. GRB 180721A: LCO Haleakala observations
  99. GRB 180720C: Swift/UVOT Upper Limits
  100. GRB 180720C: LT observations

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