In-medium omega mass from the gamma+Nb -> pi(0)gamma+X reaction
In-medium omega mass from the gamma+Nb -> pi(0)gamma+X reaction
复制标题
来自 gamma Nb -> pi(0)gamma X 反应的中欧米茄质量
DOI：
10.1103/physrevc.82.035209
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发表时间：
2010
影响因子：
3.1
通讯作者：
C. Wendel
中科院分区：
文献类型：
--
作者：
M. Nanova;V. Metag;G. Anton;J. Bacelar;O. Bartholomy;D. Bayadilov;Y. Beloglazov;R. Bogendoerfer;R. Castelijns;V. Crede;H. Dutz;A. Ehmanns;D. Elsner;K. Essig;R. Ewald;I. Fabry;M. Fuchs;C. Funke;R. Gothe;R. Gregor;A. Gridnev;E. Gutz;S. Hoeffgen;P. Hoffmeister;I. Horn;J. Hoessl;I. Jaegle;J. Junkersfeld;H. Kalinowsky;F. Klein;F. Klein;E. Klempt;M. Konrad;B. Kopf;B. Kopf;M. Kotulla;B. Krusche;J. Langheinrich;J. Langheinrich;H. Löhner;I. Lopatin;J. Lotz;S. Lugert;D. Menze;T. Mertens;J. Messchendorp;C. Morales;R. Novotný;M. Ostrick;L. Pant;H. Pee;M. Pfeiffer;A. Roy;A. Radkov;S. Schadmand;C. Schmidt;H. Schmieden;B. Schoch;S. Shende;G. Suft;A. Suele;V. Sumachev;T. Szczepanek;U. Thoma;D. Trnka;R. Varma;D. Walther;C. Weinheimer;C. Wendel
在寻找介质中的修改中，已经重新分析了关于原子核上光生Ω介子的数据。这些数据是在波恩的ELectron Stretcher Anlage（艾尔莎）加速器设施中用晶体桶（CB）/双臂光子光谱仪（TAPS）探测器系统采集的。来自数据集分析的第一结果由Trnka等人[Phys.Rev.Lett. 94，192303（2005）]，要求降低。在正常核物质密度下，核介质中的质量减少14%。被提取的。发现线形对背景减除敏感。为此，已开始对同一数据集进行重新分析，并开发了一种新的方法来减少背景，并直接从数据中确定背景的形状和绝对大小。再分析和背景测定的细节进行了描述。在再分析中提取的Nb目标上的Ω信号未显示出与作为参考测量的LH 2目标上的相应线形的偏差。因此，早期关于介质内质量转移的说法没有得到证实。不同的介质修改方案的欧米茄线形状的敏感性进行了讨论。
Data on the photoproduction of omega mesons on nuclei have been reanalyzed in a search for in-medium modifications. The data were taken with the crystal barrel (CB)/two-arm photon spectrometer (TAPS) detector system at the ELectron Stretcher Anlage (ELSA) accelerator facility in Bonn. First results from the analysis of the data set were published by Trnka et al. [Phys. Rev. Lett. 94, 192303 (2005)], claiming a lowering of the. mass in the nuclear medium by 14% at normal nuclear matter density. The extracted. line shape was found to be sensitive to the background subtraction. For this reason a reanalysis of the same data set has been initiated, and a new method has been developed to reduce the background and to determine the shape and absolute magnitude of the background directly from the data. Details of the reanalysis and of the background determination are described. The omega signal on the Nb target, extracted in the reanalysis, does not show a deviation from the corresponding line shape on a LH2 target, measured as reference. The earlier claim of an in-medium mass shift is thus not confirmed. The sensitivity of the omega line shape to different in-medium modification scenarios is discussed.