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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').
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subject:"Swift"
body:"GRB"
submitter:"Judith Racusin"

16152 results found.

  1. GRB 160123A: TAROT La Silla observatory optical observations
  2. GRB 160127A: RATIR Optical Observations
  3. GRB 160127A: TAROT La Silla observatory optical light curve
  4. GRB 160127A: Swift detection of a burst with an optical counterpart
  5. GRB 160121A: RATIR Optical Observations
  6. GRB 160121A: TSHAO optical observation
  7. GRB 160123A: NOT J-band observations
  8. GRB 160123A: Swift/UVOT Upper Limits
  9. GRB 160123A: LCOGT-SSO optical upper limit
  10. GRB 160121A: redshift from the 10.4m GTC
  11. GRB 160121A: RATIR Optical Observations
  12. GRB 160121A: Swift/UVOT Upper Limits
  13. GRB 160121A: TSHAO optical afterglow confirmation
  14. GRB 160121A: 1.8m MOA optical afterglow detection
  15. GRB 160117B: RATIR continued observations
  16. GRB 160117B: TNG spectroscopy and redshift confirmation
  17. GRB 160121A: MASTER-Amur observations
  18. GRB 160119A: VLA Detection
  19. GRB 160117B: VLA Detection
  20. GRB 160119A: afterglow confirmation from the NOT
  21. GRB 160119A: Swift/UVOT Upper Limits
  22. GRB 160119A: GROND optical/NIR afterglow observations
  23. GRB 160119A: RATIR Optical and NIR Observations
  24. GRB 160117B: RATIR Optical and NIR Observations
  25. GRB 160117B: further NOT optical observations of the afterglow
  26. GRB 160119A: NOT and GTC afterglow candidate
  27. GRB 160117B: Early iTelescope observation
  28. GRB 160117A: Swift/UVOT Upper Limits
  29. GRB 151228B: AbAO optical upper limit
  30. GRB 160104A: ISON-Ussuriysk optical observations
  31. GRB 160117B: GROND optical/NIR afterglow observations
  32. GRB 160117B: VLT/X-shooter spectroscopy
  33. GRB 160117B: iTelescope T17 optical observations
  34. GRB 160117B: NOT optical afterglow observations
  35. GRB 160117B: Swift/UVOT Detection
  36. GRB 160117B: LCOGT-SSO optical observations
  37. GRB 160117B: MASTER-Amur OT observations
  38. GRB 160117B: Swift detection of a burst with optical counterpart
  39. LIGO/Virgo G211117: INAF NOT follow-up of PanStarrs candidates
  40. GRB 160113A: Swift-XRT observations
  41. GRB 160113A: iPTF P48 Observations and Optical Transient Candidates
  42. GRB 160104A: Swift/UVOT Detection
  43. LIGO/Virgo G211117: iPTF Observations of PS15dpn
  44. GRB 160104A: Continued MITSuME Akeno Optical Observation
  45. LIGO/Virgo G211117: Subaru Hyper Suprime-Cam follow-up observation
  46. LIGO/Virgo G211117: Further Swift-XRT sources
  47. GRB 160104A: Nishi-Harima MINT Observations
  48. GRB 160104A: Mini-GWAC upper limit during prompt emission phase
  49. GRB 160104A: GWAC upper limit during prompt emission phase
  50. GRB 160104A: MITSuME Okayama upper limits
  51. GRB 160104A: Xinglong TNT optical observation
  52. LIGO/Virgo G211117: INAF TNG follow-up of Kanata telescope candidate
  53. GRB 160104A: MASTER early OT detection
  54. GRB 160104A: MITSuME Akeno Optical Observation
  55. GRB 160101A: MITSuME Akeno optical upper limits
  56. GRB 160101A: Swift/UVOT Detection
  57. LIGO/Virgo G211117: INAF TNG follow-up of MASTER OT J020906.21+013800.1
  58. LIGO/Virgo G211117: SkyMapper observations and transient candidate
  59. V404Cyg Swift Trigger 668097: AbAO optical observations
  60. GRB 151229A: MITSuME Akeno optical upper limits
  61. LIGO/Virgo G211117: Optical Observations with Kiso Schmidt telescope and KWFC
  62. LIGO/Virgo G211117: iPTF Optical Transient Candidates
  63. GRB 151229A: MITSuME Okayama upper limits
  64. GRB 151228B: MITSuME Akeno optical upper limits
  65. GRB 151229A: Swift/UVOT observations
  66. GRB 151228A: MITSuME Akeno optical upper limits
  67. GRB 151228A: T60 observations
  68. LIGO/Virgo G211117: DESGW program observations with DECam
  69. LIGO/Virgo G211117: Optical NIR observation with Kanata telescope
  70. LIGO/Virgo G211117: Optical follow-up with Kanata telescope
  71. GRB 151228B: Swift detection of a burst with an optical detection
  72. LIGO/Virgo G211117: MASTER Observations and Inspection + OT
  73. LIGO/Virgo G211117: SWASP optical observations
  74. GRB 151212A iTelescope observation
  75. V404Cyg Swift Trigger 668097: TSHAO optical observations
  76. V404Cyg Swift Trigger 668097: MASTER-Tunka optical wake up detection
  77. GRB 151215A: TSHAO optical observations
  78. GRB151215A: Continued P60 Observations
  79. GRB151215A: Early optical light curve from pt5m, La Palma
  80. GRB 151215A: MITSuME Akeno optical upper limits
  81. GRB151215A: Swift/UVOT detection
  82. GRB 151215A: MASTER early OT detection and light curve
  83. GRB 151215A: NOT spectroscopy and redshift
  84. GRB 151215A: GROND Detection of the Optical/NIR Afterglow
  85. GRB151215A: P60 Optical Afterglow Candidate
  86. GRB151212A: Swift/UVOT observations
  87. GRB 151212A: GROND Optical Afterglow Candidate
  88. GRB 151210A: Swift/UVOT Upper Limits
  89. GRB 151210A: Optical afterglow candidate from LCOGT-Cerro Tololo
  90. GRB 151205C: Optical follow-up observations at Kiso
  91. GRB 130831A: MASTER early OT detection and LC
  92. GRB 151205B: MASTER-NET early optical observations
  93. GRB 151205A: Swift/UVOT Upper Limits
  94. GRB 151127A iTelescope observation
  95. GRB 151127A: Swift/UVOT Upper Limits
  96. GRB 151127A: LCOGT-SSO optical upper limits
  97. GRB 151118A iTelescope observation
  98. GRB 151122A: Swift/UVOT Observations
  99. GRB 151027A: Maidanak optical observations
  100. GRB 151118A: MITSuME Akeno optical upper limits

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