Are there S = -2 pentaquarks?

Abstract

Recent evidence for pentaquark baryons in the channels Ξ − π − , Ξ − π + and their antiparticles claimed by the NA49 collaboration is critically confronted with the vast amount of existing data on Ξ spectroscopy which was accumulated over the past decades. It is shown that the claim is at least partially inconsistent with these data. In addition two further exotic channels of the pentaquark type available in the NA49 data are investigated. It is argued that this study leads to internal inconsistency with the purported signals.

Syne-1andSyne-2play crucial roles in myonuclear anchorage and motor neuron innervation

“…KASH domains have been shown to bind to nuclear envelope and are likely to be responsible for the association of the nuclear envelope with KASH proteins (Fischer et al, 2004;Grady et al, 2005;Malone et al, 2003;Starr and Han, 2002;Wilhelmsen et al, 2005;Yu et al, 2006;Zhang et al, 2001;Zhen et al, 2002). In C. elegans, the KASH-domain proteins UNC-83, ANC-1 and ZYG-12 have been shown to be associated with the nuclear envelope and to play roles in nuclear migration, nuclear anchorage of syncytial cells and association of centrosomes with the nuclear envelope during cell division, respectively (Hedgecock and Thomson, 1982;Horvitz and Sulston, 1980;Malone et al, 2003;Starr and Han, 2002;Starr et al, 2001).…”

Rho GTPase controls Drosophila salivary gland lumen size through regulation of the actin cytoskeleton and Moesin

“…After salivary gland cells invaginate, they undergo a phase of robust apical surface membrane growth (Myat and Andrew, 2002) and the apical domain size of individual cells decreases and elongates to become anisotropic along the longest axis of the lumen (Pirraglia et al, 2010). Apical membrane growth is limited by the basic helix-loop-helix (bHLH) transcriptional repressor Hairy and its regulation of Huckebein (Hkb), an Sp1/Egr-like transcription factor, and by target genes klarsicht (klar), which encodes a KASH-domain-containing regulator of organelle and nuclear transport (Fischer-Vize and Mosley, 1994;Fischer et al, 2004;Guo et al, 2005;Mosley-Bishop et al, 1999) and crumbs (crb), which encodes an apical membrane protein that is necessary for the establishment and maintenance of apical-basal polarity (Myat and Andrew, 2002;Tepass and Knust, 1993;Tepass et al, 1990). Apical membrane remodeling in salivary gland cells is also regulated by Ribbon (Rib), a Broad Tramtrack Bric-a-brac (BTB) domain transcription factor (Bradley and Andrew, 2001;Shim et al, 2001), which promotes Crb expression and limits apical activity of the ERM protein Moesin .…”

Strangeness observables and pentaquarks

“…This known source of systematic errors is investigated by the experiments which observe pentaquark candidates. Other authors discuss limits from the non observation of the Ξ(1860) peaks of NA49 by previous experiments [108]. These points are addressed while trying to explain the new non-observations of pentaquarks quoted above.…”

“…Recent publications discuss problems like e.g. the non-observation of these peaks by previous experiments [108] and the possibility that the observed peaks are kinematic reflections e.g. [107].…”