[논문 리뷰] The Eighteenth Data Release of the Sloan Digital Sky Surveys: Targeting and First Spectra from SDSS-V

Andrés Almeida, Scott F. Anderson외 152명|arXiv (Cornell University)|2023. 01. 18.

Astronomical Observations and Instrumentation인용 수 11

한 줄 요약

DR18은 첫 SDSS-V 데이터 릴리스로, 타깃 데이터베이스와 첫 스펙트럼을 자세히 설명하며, 약 ~25,000개의 새로운 SDSS 스펙트럼과 eFEDS X-ray 소스 스펙트럼, 더불어 소프트웨어 및 VAC 업데이트를 포함한다.

ABSTRACT

The eighteenth data release of the Sloan Digital Sky Surveys (SDSS) is the first one for SDSS-V, the fifth generation of the survey. SDSS-V comprises three primary scientific programs, or "Mappers": Milky Way Mapper (MWM), Black Hole Mapper (BHM), and Local Volume Mapper (LVM). This data release contains extensive targeting information for the two multi-object spectroscopy programs (MWM and BHM), including input catalogs and selection functions for their numerous scientific objectives. We describe the production of the targeting databases and their calibration- and scientifically-focused components. DR18 also includes ~25,000 new SDSS spectra and supplemental information for X-ray sources identified by eROSITA in its eFEDS field. We present updates to some of the SDSS software pipelines and preview changes anticipated for DR19. We also describe three value-added catalogs (VACs) based on SDSS-IV data that have been published since DR17, and one VAC based on the SDSS-V data in the eFEDS field.

연구 동기 및 목표

• Describe SDSS-V’s scientific goals and hardware, and summarize DR18 scope and data access.
• Present the MOS targeting databases, catalog cross-matching, and carton concept for SDSS-V target selection.
• Inform on new spectra, including eFEDS, and accompanying VACs and software updates.

제안 방법

• Introduce the SDSS-V MOS targeting architecture and the creation of a unified mos_catalog from cross-matched input catalogs.
• Define cartons as target selection algorithms grouped by science programs and link them to observable designs via mos_carton_to_target.
• Detail data access pathways via CAS/SAS and data models used for DR18.
• Describe the handling of eFEDS spectra and the associated VAC.
• Outline updates to SDSS software, especially the BOSS spectral reduction package.

Figure 1: Cartoon diagram of the relationships between several key database tables and of the workflow between sky sources and observed targets (§ 5.1 – 5.2 ). The objects colored yellow, blue, pink, and purple correspond to the same types of tables in Figures 2 – 4 . The green color has been repurp

실험 결과

연구 질문

• RQ1 How does DR18 organize SDSS-V targeting information and enabling schemes for MWM and BHM?
• RQ2 What new data products (spectra, cartons, VACs) are released in DR18 and how can researchers access them?
• RQ3 How are cartons and targeting generations versioned and utilized to plan future SDSS-V observations?
• RQ4 What are the updates to software pipelines and data models in DR18?

주요 결과

• DR18 provides targeting information for MWM and BHM totaling about 269.5 GB in MOS_TARGET_DIR.
• DR18 introduces the carton concept to organize targets by selection algorithm and science goals.
• Approximately 25,000 new SDSS spectra are released, including eFEDS optical spectra with 301.9 GB added to BOSS_SPECTRO_REDUX.
• New VACs based on DR17 and an updated DR15-based VAC are released alongside DR18.
• SDSS-V data access remains through CAS SkyServer and SAS with extensive tutorials and data models available.

Figure 2: Relationships between the cross-matched mos_catalog table and the original source input catalogs (§ 5.1 ). There are 17 source input catalogs that are linked to mos_catalog through the structure shown above, with “X” representing the name of the original catalog (Table 2 ).