Hadronic resonance production in $d$+Au collisions at $\sqrt{s_{_{NN}}}$ = 200 GeV at RHIC

TL;DR

This paper reports the first measurements of various hadronic resonances in deuteron-gold collisions at RHIC, analyzing their properties, spectra, and nuclear modification factors to understand particle production mechanisms.

Contribution

It provides novel measurements of resonance production and their properties in $d$+Au collisions at 200 GeV, comparing them to $p+p$ interactions and exploring nuclear effects.

Findings

Resonance spectra follow a generalized $m_T$ scaling law.

Resonance ratios are comparable between $d$+Au and $p+p$ collisions.

Nuclear modification factors scale with the number of binary collisions for $p_T > 1.2$ GeV/c.

Abstract

We present the first measurements of the $\rho(770)^0$, $K^*$(892), $\Delta$(1232)$^{++}$, $\Sigma$(1385), and $\Lambda$(1520) resonances in $d$+Au collisions at $\sqrt{s_{_{NN}}}$ = 200 GeV, reconstructed via their hadronic decay channels using the STAR detector at RHIC. The masses and widths of these resonances are studied as a function of transverse momentum ($p_T$). We observe that the resonance spectra follow a generalized scaling law with the transverse mass ($m_T$). The $<p_T>$ of resonances in minimum bias collisions is compared to the $<p_T>$ of $\pi$, $K$, and $\bar{p}$. The $\rho^0/\pi^-$, $K^*/K^-$, $\Delta^{++}/p$, $\Sigma(1385)/\Lambda$, and $\Lambda(1520)/\Lambda$ ratios in $d$+Au collisions are compared to the measurements in minimum bias $p+p$ interactions, where we observe that both measurements are comparable. The nuclear modification factors ($R_{dAu}$) of the $\rho^0$, $K^*$, and $\Sigma^*$ scale with the number of binary collisions ($N_{bin}$) for $p_T >$ 1.2 GeV/$c$.