A novel phenomenological approach to total charm cross section measurements at the LHC

Measuring the total charm cross section is important for the comparison to theoretical predictions of the highest precision available for charm today, which are completely known up to NNLO QCD for the total inclusive cross sections. These are also independent of charm fragmentation, while practical measurements of charm hadrons in a fiducial phase space are not. Recently the LHC experiments have reported non-universality of charm fragmentation, which shows that e.g. charm baryon-to-meson ratios are not universal in different collision systems, and that the related production fractions also depend on transverse momentum. This breaks the charm fragmentation universality that was assumed until recently for the extrapolation of experimental measurements to the full total charm cross section phase space. A proposal is made how to address this non-universality in a data driven way without the need to implement any particular non-universal fragmentation model. As a practical example, this method is applied to the extrapolation of published LHC measurements of $D^0$ production at $\sqrt{s}=5$ TeV to the corresponding total charm cross section, which fully accounts for charm fragmentation non-universality for the first time. The result, $8.43 ^{+1.05}_{-1.16}(\text{total})$ mb, differs substantially from the one assuming charm fragmentation universality, but still compares well to theoretical QCD predictions up to NNLO.Comment: to appear in Proceedings of the European Physical Society Conference on High Energy Physics (EPS-HEP2023

Myeloid-Derived Suppressor Cells Are Controlled by Regulatory T Cells via TGF-β during Murine Colitis

Myeloid-derived suppressor cells (MDSCs) are well known regulators of regulatory T cells (Treg cells); however, the direct regulation of MDSCs by Treg cells has not been well characterized. We find that colitis caused by functional deficiency of Treg cells leads to altered expansion and reduced function of MDSCs. During differentiation of MDSCs in vitro from bone marrow cells, Treg cells enhanced MDSC function and controlled their differentiation through a mechanism involving transforming growth factor-β (TGF-β). TGF-β-deficient Treg cells were not able to regulate MDSC function in an experimentally induced model of colitis. Finally, we evaluated the therapeutic effect of TGF-β-mediated in-vitro-differentiated MDSCs on colitis. Adoptive transfer of MDSCs that differentiated with TGF-β led to better colitis prevention than the transfer of MDSCs that differentiated without TGF-β. Our results demonstrate an interaction between Treg cells and MDSCs that contributes to the regulation of MDSC proliferation and the acquisition of immunosuppressive functions

Illustration of the performance of the CMS tracker and reconstruction on early Run 3 data, on the example of D* meson reconstruction

In this poster some of the first distributions from CMS Run 3, showing a signal for charm production in Minimum Bias data taken at the injection center-of-mass energy of 900 GeV, are shown as an illustration of the readiness of CMS for data taking in Run 3, with particular focus on the tracker, tracking, and vertexing performance at low transverse momenta

Measurement of the CMS offline tracking efficiencyfrom the ratio of reconstructed D∗ and D0 mesons

The efficiency for offline track reconstruction in CMS is measured directly from the data using a novel method. This method is based on taking the ratio of charm mesons reconstructed in the decay chains $D^{*\pm} \rightarrow K^{\mp}\pi^{\pm}\pi_s^{\pm}$ and $D^0 \rightarrow K^{\mp}\pi^{\pm}$, using the special kinematics of the so-called 'slow pion' $\pi_s$ from $D^*$ decay. It also requires the treatment of the a priori unknown mixture of prompt (from charm) and non-prompt (from beauty) contributions to the final states. Details of the method are explained and first results for the actual tracking efficiencies are presented

Heavy flavour production at CMS: D Meson Production, B Meson Production & Rare B Meson Decays to Two Muons

This talk presents recent results about heavy flavor production at CMS

Horizontal change of philtrum after orthognathic surgery in patients with facial asymmetry

Background Soft tissue asymmetry such as lip canting or deviation of the philtrum is an important influencing factor for unbalanced facial appearance. Lip canting could be improved by the correction of the occlusal canting or positional change of the mentum. Although there are many studies about changes of lip canting, however, postoperative changes of philtrum deviation have not been yet reported. In this study, we investigate the positional change of the philtrum after orthognathic surgery and influencing factors. Methods Positional change of the philtrum was evaluated in 41 patients with facial asymmetry who underwent bimaxillary surgery, in relation to other anatomical soft tissue landmarks using a frontal clinical photo. The surgical movement of the maxillary and mandibular dental midline and canting were measured in postero-anterior cephalogram before and 1 day after surgery. The same procedure was repeated in patients with more than 1.5 mm perioperative change of the mandibular dental midline after bimaxillary surgery. Results Maxillary dental midline shifting and canting correction did not have a significant correlation with lateral movement of the philtrum midline. However, the mandibular shift had a statistically significant correlation with a lateral movement of the philtrum (p < 0.05) as well as other linear parameters and angle values. Conclusion The horizontal change of the philtrum is influenced by lateral mandibular movement in patients with facial asymmetry, rather than maxillary lateral movement

Measurement of D* meson cross sections in the full phase space for charm in CMS

This is a summary talk about total, single- and double-differential cross sections for charm which are measured from the reconstruction of charm hadronic states in the CMS detector. Among all the hadronic states of charm, for this talk especially the reconstruction of D* which decays into D0 and a slow pion is introduced at proton-proton center-of-mass energies of 0.9, 5, 7, and 13 TeV. The measured cross sections for this final state show consistency compared to QCD theory and also to other LHC experiments. Then the D* meson cross sections measured in the full phase space accessible with the CMS detector are extrapolated to extract the total charm cross section. For the first time, this extrapolation applies the pT-dependent cross-section ratios between meson and baryon of charm, which are recently measured from LHC experiments

Partial Edge Dislocations Comprised of Metallic Ga Bonds in Heteroepitaxial GaN

We investigated the atomic structure of inclined threading edge dislocation (TED) typically observed in GaN grown on Si(111) through (scanning) transmission electron microscopy. Atomic observations verified that the inclined TED consisted of two partial dislocations. These results imply that the inclined TED possesses a Ga–Ga atomic configuration that is energetically unfavorable. However, the introduction of such structures is considered unavoidable because the TEDs should climb regularly to mediate the applied stress or the increasing surface due to the buffer layer. This Ga–Ga configuration is highly likely to form metallic bonds and appears to be the primary reason for the inferior efficacy of a GaN light-emitting diode grown on Si(111)