FIRST巡天数据

FIRST巡天计划的设计目标是获得帕洛玛天图（POSS）在南北银冠区域一万多平方度天区的射电波段暗弱图像。使用美国国家射电天文台（NRAO）甚大阵列（VLA）和自动化图像处理流水线，FIRST巡天项目生成了1.8角秒像素、典型均方根值为0.15 mJy、分辨率为5角秒的图像。在1 mJy源检测阈值下，每平方度有约90个源，其中约35%的源在2-30“的尺度上具有解析出的结构。FIRST巡天30%的源能够在斯隆数字巡天找到对应体。此镜像数据集包括星表和图像，图像数据存储于两个子目录下image/vla_first/data/和image/naro_first/，其中，第一个目录包含完整的数据，第二个目录是第一个目录的子集，数据量小更易于分享和传播，它可以被第一个目录完全取代；星表数据存储于catalog目录。

The FIRST Survey was designed to acquire faint radio images of over 10,000 square degrees of the northern and southern galactic cap regions covered by the Palomar Observatory Sky Survey (POSS). Utilizing the Very Large Array (VLA) of the National Radio Astronomy Observatory (NRAO) and an automated image processing pipeline, the FIRST Survey generated images with 1.8 arcsecond pixels, a typical root-mean-square (RMS) noise level of 0.15 mJy, and a spatial resolution of 5 arcseconds. At a source detection threshold of 1 mJy, there are approximately 90 sources per square degree, and roughly 35% of these sources exhibit resolved structures on scales of 2–30 arcseconds. Thirty percent of the sources detected by the FIRST Survey have counterparts identified in the Sloan Digital Sky Survey (SDSS). This mirrored dataset includes catalogs and image data. The image data is stored in two subdirectories: image/vla_first/data/ and image/naro_first/. The first directory contains the full dataset, while the second is a subset with a smaller data volume that enables easier sharing and dissemination, and can be fully replaced by the first directory. Catalog data is stored in the catalog directory.

搜集汇总

背景与挑战

背景概述

FIRST巡天数据是一个射电波段巡天数据集，旨在通过美国国家射电天文台的甚大阵列获取帕洛玛天图区域的高分辨率暗弱图像，典型分辨率为5角秒，均方根值为0.15 mJy。数据集包括星表和图像，总数据量345.01 GB，覆盖射电、恒星和星系等关键词，适用于科研用途，特别是宇宙学、星系和恒星与星际物质研究。