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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').
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"

21797 results found.

  1. Magellan Observations of GRB030725 (=H2779)
  2. XRF 020427: Gemini-South Spectroscopic Observations of the Host
  3. XRF030824: Optical observations
  4. IBAS detection of bursts from SGR 1806-20
  5. Radio Observations of SGR1806-20
  6. INTEGRAL ToO OBSERVATIONS OF SGR1806-20: CALL FOR CORRELATED OBSERVATIONS
  7. XRF030824: Second-epoch Palomar observations
  8. XRF030824: optical observations
  9. GRB030823: optical observations
  10. GRB030823: Palomar observations
  11. XRF030824: Palomar observations
  12. RAPTOR observations of GRB030823
  13. Lulin follow-up observations of GRB030823
  14. GRB 030817 = H2808 TAROT optical observations
  15. SGR 1808-20 (=H2802): A Possible new SGR
  16. GRB 021206 Optical Observations
  17. XRF030723(=H2777): Chandra Fading X-ray Afterglow Confirmed
  18. XRF 030723: Detection of a rebrightening in the optical afterglow
  19. GRB030725: Optical observations
  20. GRB021206 optical counterpart upper limit
  21. XRF030723: Re-analysis of ROTSE-III early images
  22. XRF030723 (=H2777): Second Epoch Magellan Observations
  23. GRB 030725: optical observations.
  24. GRB030725, optical transient observations
  25. XRF030723 Radio Observations
  26. XRF 030723: confirmation of fading optical counterpart
  27. XRF030723(=H2777): Chandra Observations
  28. XRF 030723: VLT spectra
  29. Magellan Observations of XRF030723 (=H2777)
  30. GRB030723: Upper limits from historical observations
  31. GRB030725, possible optical transient
  32. XRF030723: Palomar observations and proposed counterpart
  33. XRF030723: optical observations
  34. XRF030723 (= H2777): Chandra Observations Scheduled
  35. XRF030723, ROTSE-III Early Observations
  36. XRF030723, BVRcIc field photometry
  37. XRF 030723, optical observations
  38. XRF030723, optical observations
  39. XRF 030723, optical observations
  40. GRB030723, optical observations
  41. Konus-Wind detection of the bursts from SGR1806-20 region
  42. SGR 1806-20, submm observations
  43. RXTE PCA Observations of SGR1806-20 Region
  44. GRB030329: RTT150 optical observations
  45. GRB030329, optical observation in May
  46. GRB030418: R optical observations
  47. GRB 021206, Radio afterglow candidate
  48. GRB030528(=H2724): X-ray Afterglow Identified in Second Epoch
  49. GRB030329, SPM optical observations (Correction of GCN2075 R band)
  50. GRB 030528: Infrared Observations and the Proposed IR Counterpart
  51. GRB 030528: Optical Observations
  52. GRB 030528, radio observations
  53. GRB030528(=H2724): Observations with the Chandra X-ray Observatory
  54. GRB030329, further radio observations at GMRT
  55. GRB030329, SPM optical observations
  56. GRB030528: Chandra TOO Planned
  57. GRB 030519B: optical observations.
  58. MASTER: optical observation GRB030601
  59. GRB 030329: optical observations
  60. GRB 030329/SN 2003dh: Jitter Episode
  61. GRB 030329: Optical Observations
  62. GRB 030528: Optical observations at RIKEN
  63. GRB 030416: Optical Observations
  64. GRB030329, Optical observations
  65. GRB 030329/SN 2003dh: Possible increase in brightness
  66. GRB 030329: HST ACS Observations of the Host
  67. GRB 030329 Optical Observations
  68. GRB030329: XMM-Newton observation
  69. GRB 021004: HST observations
  70. GRB030324: Further Observations of the Candidate Optical Afterglow
  71. GRB030519B (=H2716): Peak Fluxes, Fluences, and Energy Spectrum
  72. GRB 030418: Second Epoch Optical Observations with Magellan
  73. HETE GRB030329, correction to Rc Observations in Loiano
  74. GRB030329: RTT150 optical observations
  75. GRB030329, BVRI photometry
  76. GRB 030429: Redshift of neighbor galaxy
  77. GRB 030329: High-Resolution Spectroscopy of the Host
  78. GRB030429: RTT150 optical observations, a possible host galaxy
  79. GRB030329: RTT150 optical observations and upper limit for a host
  80. GRB030501, optical observation
  81. GRB030329: RTT150 optical observations and upper limit for a host
  82. GRB 030429: Radio Observations
  83. GRB 030429: IR photometry with IRSF/SIRIUS
  84. GRB 030329 Optical Observations
  85. GRB030429: Optical Observations
  86. GRB 030501: TAROT possible candidate counterpart
  87. GRB 030429: confirmation of afterglow candidate
  88. GRB030429, possible optical counterpart
  89. GRB 030329 Oprical observations in Rozhen observatory
  90. GRB 030429: ROTSE-III observations
  91. GRB 030324: Radio Observations
  92. GRB030329 observed as a sudden ionospheric disturbance (SID)
  93. GRB030329, SPM optical observations (Correction)
  94. GRB030329, SPM optical observations
  95. GRB 030329, the review of the sky area in plate archive (1950-1998)
  96. Optical Observations of GRB 030418 with Magellan
  97. GRB 030329: optical spectropolarimetry at VLT
  98. GRB030329: optical polarization
  99. GRB 030329 3.5 and 6 cm radio observations at RTF-32 telescope
  100. MASTER:optical observations GRB030418

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