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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.

Advanced Search Examples (click to copy):

subject:"Swift"
body:"GRB"
submitter:"Judith Racusin"

26038 results found.

  1. GRB030329: radio observations at RT-22 (CrAO)
  2. XRF 030723: Detection of the likely host galaxy
  3. GRB030913: Subaru Optical Observations
  4. GRB030913, candidate afterglow observations
  5. GRB030913: AAVSO optical observations
  6. GRB030913 (=H2849): Confirmation of the Flight Localization
  7. Magellan Observations of GRB030725 (=H2779)
  8. GRB030913 (=H2849): A GRB Possibly Localized by HETE
  9. GRB 030824: Candidate Afterglow (or Variable/Flare Star?)
  10. GRB 021206 Optical Observations
  11. XRF030723(=H2777): Chandra Fading X-ray Afterglow Confirmed
  12. XRF 030723: Detection of a rebrightening in the optical afterglow
  13. GRB030725: Optical observations
  14. XRF030723, BVRcIc field photometry update
  15. XRF030723: Re-analysis of ROTSE-III early images
  16. GRB030725, optical transient observations
  17. XRF030723 Radio Observations
  18. XRF030723(=H2777): Chandra Observations
  19. XRF 030723: VLT spectra
  20. GRBlog: Compilation of all GCN Circ. data
  21. GRB030329: second XMM-Newton observation
  22. GRB030418: R optical observations
  23. GRB 021206, Radio afterglow candidate
  24. GRB030528(=H2724): X-ray Afterglow Identified in Second Epoch
  25. GRB 030528: Infrared Observations and the Proposed IR Counterpart
  26. GRB 030528: Optical Observations
  27. GRB 030528: tentative NIR counterpart
  28. GRB030329, further radio observations at GMRT
  29. GRB 030519B: optical observations.
  30. GRB 030329: optical observations
  31. GRB 030329: Correction to GCN 2254
  32. GRB 030329: Optical Observations
  33. GRB 021004: HST observations
  34. GRB030324: Further Observations of the Candidate Optical Afterglow
  35. GRB 030418: Second Epoch Optical Observations with Magellan
  36. GRB 030329: Optical limit (contemporaneous imaging)
  37. GRB030329: RTT150 optical observations
  38. GRB 030329: Optical limit (contemporaneous photography)
  39. GRB 030429: Redshift of neighbor galaxy
  40. GRB030429: RTT150 optical observations, a possible host galaxy
  41. GRB030329: RTT150 optical observations and upper limit for a host
  42. GRB 030329: all-sky CCD images by K. Shiokawa immediately after the burst
  43. GRB030329: RTT150 optical observations and upper limit for a host
  44. GRB 030429: redshift from VLT spectroscopy
  45. GRB 030429: IR photometry with IRSF/SIRIUS
  46. GRB 030329 Optical Observations
  47. GRB030501: TAROT candidate afterglow present in archival images
  48. GRB 030429: confirmation of afterglow candidate
  49. GRB 030329 Oprical observations in Rozhen observatory
  50. GRB 030324: Radio Observations
  51. SNeIa AS THE POSSIBLE PROGENITORS OF SHORT-DURATION GRBs.
  52. GRB 030329: Spectral Evolution of SN 2003dh
  53. Optical Observations of GRB 030418 with Magellan
  54. GRB 030329: optical spectropolarimetry at VLT
  55. GRB 030329: wide-field photograph by R. Tamura 1 hr after the burst
  56. GRB030418: Kiso near infrared observations
  57. GRB 030418: Optical afterglow
  58. GRB 030418: Finder for afterglow candidate
  59. GRB 030418: Optical afterglow candidate
  60. GRB030329, UBVRI polarimetry, R-polarization
  61. GRB 030329: SARA Optical Observations
  62. GRB030329: VR Photometry at TNG
  63. GRB030324: Candidate Optical Afterglow (Erratum)
  64. GRB030324: Candidate Optical Afterglow
  65. GRB 030329 Rc observations
  66. Superluminal motion in GRB 030329 (Correction)
  67. Superluminal motion in GRB 030329
  68. GRB 030329 and SN 2003dh
  69. GRB 030329 VLBA Observations
  70. GRB 030329: BVRI photometry at Asiago
  71. GRB 030329: Supernova Confirmed
  72. GRB030329: RTT150 optical observations
  73. GRB030329: Near Infrared Observations at Gunma
  74. Kiso observation of the GRB030329 at April 6
  75. GRB 030329 Optical observations
  76. GRB 030329, color evolution
  77. GRB 030329: possible color change
  78. GRB030329: RTT150 optical observations
  79. GRB 030329: Supernova Spectrum Emerging
  80. GRB030329: Kiso B and R band observations
  81. GRB030329: RTT150 optical observation
  82. GRB 030329: SARA Optical Observations
  83. GRB 030329: SARA Optical Observations
  84. GRB030329, fading resumes
  85. GRB 030329, Optical observations
  86. GRB 030329, nearby galaxies
  87. GRB030329 Radio 23/43/90 GHz observations at Nobeyama
  88. GRB 030329: Sub-millimeter detection
  89. GRB 030329: SARA Optical Observations
  90. GRB 030329: SARA Optical Observations
  91. GRB030329, new UBVRcIc field photometry
  92. GRB 030329, light curve and SN prediction
  93. GRB030329: optical observations at Tokyo Tech
  94. GRB 030329: optical observations
  95. GRB030329: multiple re-brightening phases
  96. GRB030328: Full Observation, X-ray Fading and Spectrum Measured
  97. GRB 030329 , SPM optical observations
  98. Further AAVSO V,B,R observations of GRB030329
  99. GRB 030329: SARA Optical Observations
  100. GRB 030329: Observations with ANDICAM

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