English (United Kingdom)

https://curated-unify.zendy.io/wp-json/zendy-region/v1/featured_content/oa?rat=en

https://curated-unify.zendy.io/wp-json/zendy-region/v1/highlighted_journal/

Global: Zendy Plus annual

Presents the access of premium content as premium feature

Premium Content

Presents the keyphrase highlighting as premium feature

Keyphrase Highlighting

Presents the summarisation as premium feature

Summarisation

Insights

Presents the pdf analysis as premium feature

PDF Analysis

Presents the zaia usage as premium feature

ZAIA

Global: Zendy Tools annual

Global: Zendy Free Plan

Global: Zendy Tools monthly

Global: Zendy Plus monthly

We present the first measurements of [Formula: see text] pair production at very low transverse momentum ([Formula: see text] 0.15 GeV/[Formula: see text]) in Au + Au collisions at [Formula: see text] = 200 GeV and U + U collisions at [Formula: see text] = 193 GeV using the STAR detector at the Relativistic Heavy Ion Collider. A significant excess, with respect to known hadronic contributions, is observed in 60-80% central heavy-ion collisions over the whole [Formula: see text] range. Remarkably, the excess almost entirely happens below [Formula: see text] 0.15 GeV/[Formula: see text], and can not be explained by a theoretical model calculation incorporating in-medium broadened [Formula: see text] spectral function. Moreover, the observed excess yield has no significant centrality dependence. In addition, the steepness of [Formula: see text] distribution exhibits mild invariant mass and collision species dependence.

e+e− Pair Production at Very Low Transverse Mometum in Au+Au Collisions at s NN = 200 GeV and U+U Collisions at sNN = 193 GeV at STAR