Bibliometric benchmarking across astronomy journals: Knowledge-use cycle and PASJ in the global landscape

TL;DR

This study benchmarks PASJ against eight astronomy journals (1996–2024) using Scopus/SciVal-derived indicators to map the knowledge-use cycle in the field. It finds a multi-year maturation of citation impact (rise within ~2–4 years, saturation by ~10–12 years) and shows that PASJ generally underperforms the world baseline, though it experiences episodic boosts from special issues tied to facilities or missions. The analysis highlights a strong, persistent advantage for high-volume journals (ApJ, MNRAS, A&A) and relatively higher internationalization in those venues, while PASJ lags in collaboration and top-tier citation metrics. Practical recommendations for PASJ include organizing well-timed, facility-focused special issues and increasing international collaboration to enhance visibility, alongside adopting long-window indicators to accurately capture long-term influence.

Abstract

We present a comparative bibliometric analysis of eight astronomy journals over 1996--2024, including \textit{Publications of the Astronomical Society of Japan} (PASJ). Using data from Scopus and SciVal, we extract annual indicators of publication activity and scholarly impact, analyze time series, citation distributions, and citation age profiles, and benchmark PASJ within this landscape. The age profiles reveal a characteristic knowledge-use cycle: citations rise over $\sim$2--4 years, approach saturation by $\sim$10--12 years, underscoring limits of short-window impact metrics. Journals published by European and North American astronomical organizations sustain higher impact, whereas PASJ generally lies below the world baseline. In parallel, PASJ shows episodic above-baseline impact through facility- or mission-driven special issues and features that, given the journal's modest annual volume, can materially shift year-level metrics. These patterns point to two potential avenues for PASJ: well-timed, thoughtfully organized special issues and features that highlight high-impact results, and continued strengthening of international collaboration.

Figures (9)

• Figure 1: Annual number of peer-reviewed articles (Scholarly Output) published from 1996 to 2024 in selected astronomy journals. The black dashed line represents the total scholarly output in the "Entire Area" as indexed in Scopus. The vertical axis is logarithmic. Alt text: A line graph with a logarithmic vertical axis. The x-axis shows publication years from 1996 to 2024. The y-axis represents the number of peer-reviewed journal articles, ranging from about 30 to about 30,000. Eight colored lines trace individual journals, and a black dashed line shows the "Entire Area" total.
• Figure 2: Annual share of internationally co-authored peer-reviewed articles (International Collaboration) from 1996 to 2024 in selected astronomy journals. A&A shows the highest and most sustained collaboration rates, followed by MNRAS, ApJ, and AJ; Nat. Astron. has remained high since 2017. PASJ records the lowest values across the period, and PASP tracks slightly higher levels. The black dashed line marks the "Entire Area" average. The vertical axis is linear and reports percentages. Alt text: A line graph with a linear vertical axis. The x-axis shows publication years from 1996 to 2024. The y-axis shows the share of internationally co-authored papers (percent), ranging from 0% to 100%. Multiple colored lines represent individual journals and a black dashed line shows the "Entire Area" average.
• Figure 3: Annual trends in CPP from 1996 to 2024 across major astronomy journals. CPP values remain relatively stable for articles published before 2010, but decline sharply for more recent publication years. This pattern reflects the effects of citation aging and temporal bias: articles typically accumulate citations over a 10--15 year window, and recent papers have not yet had time to reach their full citation potential. These results highlight the importance of accounting for time-based citation dynamics when interpreting bibliometric indicators. Alt text: A line chart showing Citations per Publication (CPP) by publication year from 1996 to 2024 for eight astronomy journals and an Entire Area baseline.
• Figure 4: Annual FWCI for selected astronomy journals from 1996 to 2024. FWCI is computed from citations received during the publication year and the subsequent three calendar years and is normalized by field, publication year, and publication type; 1.0 corresponds to the world average. Values for 2022 and later (shaded in gray) are provisional as of June 2025 because the four-year window is incomplete. Nat. Astron. shows the highest and most consistent FWCI values since its launch. ApJS exhibits large annual variation but frequently exceeds 2.0. In contrast, PASJ remains consistently below the global average. Alt text: A line graph with a linear vertical axis showing FWCI trends for eight astronomy journals from 1996 to 2024. Each line represents a journal. Values for 2022 onward are shaded in gray to indicate that citation windows are incomplete. Nat. Astron. shows the highest values, followed by ApJS. PASJ remains consistently below the average.
• Figure 5: Annual Top 10% publication proportion for each journal, 1996--2024. ApJ and MNRAS consistently maintain higher proportions, typically between 30--40%, while PASJ and PASP remain below the global average throughout the period. These results reflect differences in overall citation impact and visibility across journals. Alt text: A line graph with a linear vertical axis showing trends of annual Top 10% publication proportion for eight astronomy journals from 1996 to 2024. Each line represents a journal. Values for 2022 onward are shaded in gray to indicate that citation windows are incomplete. Nat. Astron. shows the highest values, followed by ApJS. PASJ remains consistently below the average.