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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"

10826 results found.

  1. GRB 070328 : Suzaku ToO follow up starts
  2. Short-Hard GRB 070209: PROMPT Observations
  3. GRB 070311: a long GRB detected by INTEGRAL
  4. GRB 070125: Chandra X-ray Confirmation of Jet Break
  5. GRB 070309: A long GRB detected by INTEGRAL
  6. GRB 070306: XRT Team Refined Analysis
  7. GRB 070227: optical observations
  8. GRB 070227: optical observations
  9. GRB 070224: SARA upper limit
  10. GRB 070224, Swift-BAT refined analysis
  11. GRB 070224: MASTER-Net refind analysis
  12. GRB 070224: MASTER-VWF-Kislovodsk observations
  13. GRB 070224: MASTER observations
  14. GRB 070224: Swift detection of a burst
  15. GRB 070223: Optical observations
  16. RHESSI Spectrum of GRB070220
  17. GRB 070223, Swift-BAT refined analysis
  18. Konus-Wind and Konus-A observations of GRB 070220
  19. GRB 070220: MITSuME Okayama Optical Observation
  20. GRB 070220: ART-3 Optical and NIR limits
  21. GRB 070220: Observation with the KANATA 1.5m telescope
  22. GRB070219: MASTER-VWF-Kislovodsk observations
  23. GRB 070219, Swift-BAT refined analysis
  24. GRB 070219: ROTSE-III Optical Limits
  25. GRB070219 - SDSS Pre-Burst Observations
  26. GRB 070201: clarification on localization and Konus-Wind spectra
  27. IPN localization of very bright long hard GRB 070207
  28. IPN localization of very intense short GRB 070201
  29. GRB 070208: ROTSE-III Optical Limits
  30. GRB 070125: further AAVSO optical observations
  31. GRB 070129, Swift-BAT refined analysis of a particularly long
  32. Konus-Wind observation of GRB 070125
  33. GRB070125: Swift-XRT Refined Analysis
  34. GRB 070125: SARA detection in R
  35. RHESSI Spectrum of GRB070125
  36. Konus-Wind observation of short hard GRB 070124
  37. IPN localization of GRB070124 (short duration, hard spectrum)
  38. GRB 070110: Continued Detection and Request for Ground Followup
  39. GRB 070110: Ep,i - Eiso correlation
  40. GRB 070110 declared a "Burst of Interest" by Swift team
  41. Further Retractions of previous Swift-BAT triggers
  42. Trigger 255685: Swift detection of a possible burst
  43. GRB 070103: Swift detection of a burst
  44. Retractions of previous Swift-BAT triggers
  45. Konus-Wind observation of GRB 061222A
  46. GRB 061210: Swift/XRT Astrometry Correction
  47. GRB061222B: Swift-XRT Refined Analysis
  48. GRB 061222B: SARA upper limit
  49. GRB 061222A: Prompt ROTSE-III Optical Limits
  50. GRB 061217: Astrometry-Corrected XRT Position
  51. GRB 061217, SMARTS optical observations
  52. GRB 061217: ROTSE-III Optical Limits
  53. GRB 061214(?): ROTSE-III Optical Limits
  54. GRB 061210: Suzaku WAM observation of the prompt emission
  55. GRB 061210: Swift-BAT detection of a short burst
  56. Konus-Wind observation of GRB 061201
  57. GRB 061202, Swift-BAT refined analysis
  58. GRB 061122: GETS observation
  59. GRB 061121: Second Epoch ATCA Radio Observations
  60. GRB 061126: optical observation
  61. GRB 061126: Tautenburg afterglow observations
  62. GRB 061121: MDM Continued Monitoring
  63. GRB 061121: MDM Optical Decay
  64. GRB 061121: ART detection in Ic
  65. Konus-Wind observation of GRB 061122
  66. Konus-Wind and Konus-A observations of GRB 061121
  67. INTEGRAL results on GRB 061122
  68. GRB 061122A: a long GRB detected by INTEGRAL
  69. GRB 061121, Swift-BAT refined analysis
  70. GRB 061121: Faulkes Telescope North Optical Observation
  71. GRB 060111B: Swift UVOT Refined Magnitudes
  72. GRB061110B: Optical observations at Crni Vrh
  73. GRB 061110B: NOT optical observations
  74. GRB 061110: ROTSE-III Optical Limits
  75. GRB061019: second epoch CrAO observations
  76. GRB061102B: Super-LOTIS observations
  77. GRB 061028: Optical R passband observations
  78. GRB 061028: z band imaging
  79. GRB 061027, Swift refined analysis of a possible burst
  80. GRB061025: Swift XRT refined analysis
  81. GRB 061025: Gemini-S observations
  82. GRB061025: Swift XRT position
  83. GRB 061025: ROTSE-III Optical Limits
  84. GRB 061025: a long GRB detected by INTEGRAL
  85. Konus-Wind observation of GRB 061021
  86. GRB 061021: Swift-XRT refined analysis
  87. GRB 061021: Swift detection of a burst
  88. GRB061019: optical observations
  89. GRB 061019: SARA upper limit
  90. GRB 060930: MARGE Optical Limits
  91. GRB 061019, Swift-BAT refined analysis
  92. GRB 061019: Swift-BAT detection of a burst
  93. GRB 061007: RHESSI Spectral Fit
  94. Konus-Wind observation of GRB 061007
  95. Konus-Wind observation of the short hard GRB 061006
  96. Konus-Wind observation of GRB 060928
  97. GRB 060928: RHESSI Spectral Fit
  98. GRB 060930: near-IR afterglow candidate
  99. GRB 061002, Swift-BAT refined analysis
  100. GRB061002: MASTER-VWF-Kislovodsk observations

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