The Five-hundred-meter Aperture Spherical Telescope （FAST） will begin its early-science oper- ations during 2016. Drift-scan pulsar surveys will be carried out during this period using an ultra-wide-band receiver sy...The Five-hundred-meter Aperture Spherical Telescope （FAST） will begin its early-science oper- ations during 2016. Drift-scan pulsar surveys will be carried out during this period using an ultra-wide-band receiver system （covering - 270 to 1620 MHz）. We describe a method for accounting for the changes in the telescope beam shape and the pulsar parameters when searching for pulsars over such a wide bandwidth. We applied this method to simulated data sets of pulsars in globular clusters that are visible to FAST and found that a representative observation would have a sensitivity of -40 ply. Our results showed that a sin- gle drift-scan （lasting less than a minute） is likely to find at least one pulsar for observations of four globular clusters. Repeated observations will increase the likely number of detections. We found that pulsars in - 16 clusters are likely to be found if the data from 100 drift-scan observations of each cluster are incoherently combined.展开更多
为了提高漂移扫描CCD的识别速度,实现同步卫星实时定轨,提出基于数字信号处理器(DSP,digital signal processor)的星图快速识别算法。在嵌入式DSP数据处理平台上优化传统的三角形识别算法,采用二次匹配识别算法,即分区间筛选子星表中参...为了提高漂移扫描CCD的识别速度,实现同步卫星实时定轨,提出基于数字信号处理器(DSP,digital signal processor)的星图快速识别算法。在嵌入式DSP数据处理平台上优化传统的三角形识别算法,采用二次匹配识别算法,即分区间筛选子星表中参考星参与初匹配,利用初匹配结果推算CCD底片模型,根据背景恒星与子星表参考星的对应关系将所有恒星进行二次匹配。对分辨率为1 528×1 528实拍星图的实验处理结果表明,由于引入了DSP与改进了识别算法,在很大程度上加快了漂移扫描CCD星图识别速度,所耗时间仅为传统星图识别算法的50%,且识别成功率达到98.4%。展开更多
基金the support from the professorship award under the Chinese Academy of Sciences(CAS) President's International Fellowship Initiative(PIFI) in 2015the support from the Guizhou Scientific Collaboration Program (No.20130421)+3 种基金the support from the National Natural Science Foundation of China(NSFC, Nos.11305133 and 11273020)the support from NSFC(No.Y411101N01)the support from NSFC(No.11103045)grants from NSFC (No.11373038)the support by National Basic Research Program of China(973 program) Nos.2012CB821800 and 2015CB57100
文摘The Five-hundred-meter Aperture Spherical Telescope （FAST） will begin its early-science oper- ations during 2016. Drift-scan pulsar surveys will be carried out during this period using an ultra-wide-band receiver system （covering - 270 to 1620 MHz）. We describe a method for accounting for the changes in the telescope beam shape and the pulsar parameters when searching for pulsars over such a wide bandwidth. We applied this method to simulated data sets of pulsars in globular clusters that are visible to FAST and found that a representative observation would have a sensitivity of -40 ply. Our results showed that a sin- gle drift-scan （lasting less than a minute） is likely to find at least one pulsar for observations of four globular clusters. Repeated observations will increase the likely number of detections. We found that pulsars in - 16 clusters are likely to be found if the data from 100 drift-scan observations of each cluster are incoherently combined.
文摘为了提高漂移扫描CCD的识别速度,实现同步卫星实时定轨,提出基于数字信号处理器(DSP,digital signal processor)的星图快速识别算法。在嵌入式DSP数据处理平台上优化传统的三角形识别算法,采用二次匹配识别算法,即分区间筛选子星表中参考星参与初匹配,利用初匹配结果推算CCD底片模型,根据背景恒星与子星表参考星的对应关系将所有恒星进行二次匹配。对分辨率为1 528×1 528实拍星图的实验处理结果表明,由于引入了DSP与改进了识别算法,在很大程度上加快了漂移扫描CCD星图识别速度,所耗时间仅为传统星图识别算法的50%,且识别成功率达到98.4%。
基金supported by the Chinese National Natural Science Foundation(Nos.10878022,10903022,10903030)the Knowledge Innovation Project of CAS(KJCX2-yW-T13)+1 种基金the State Agency on Science,Innovation and Information of the Ministry for Education and Science of Ukrainethe Russian Foundation of Basic Research~~
