[en] Using the ARGUS detector at the DORIS II e⁺e^- storage ring at DESY, we have obtained evidence for a new charmed resonance which decays into D/sup asteriskplus-or-minus/(2010)π^-+. The observed mass and width are 2420 +- 6 MeV/c² and 70 +- 21 MeV/c², respectively. The fragmentation function is found to be hard, as expected for a state containing a leading charm quark produced by nonresonant e⁺e^- annihilation

[en] The associated risk factors for the majority of patients with head and neck squamous cell carcinoma (HNSCC) are tobacco and betel nut abuse, while there also seems to be a rising proportion of patients who report no history of tobacco or betel nut usage. Therefore, objective of the study was to find out potential risk factors and demographics of HNSCC patients addicted to tobacco and/or betel nut, as well as non-addicted patients. Methods: This epidemiological study was conducted in Karachi Institute of Biotechnology and Genetic Engineering (KIBGE), University of Karachi, and Jinnah Postgraduate Medical Centre (JPMC) from January to December 2016. All subjects were participants in an epidemiological study of HNSCC. Demographics and clinical characteristics were obtained for 185 addicted and 26 non-addicted patients. Results: Non-addicted patients were more likely to be females ( 2=19.0, p<0.001) and were significantly younger than addicted patients ( 2=21.0, p<0.001). Addicted patients more likely belonged to a lower income group ( 2=14.4, p=0.006) and had a higher proportion of oral cancers ( 2=30.0, p<0.001). Almost all addicted females had oral cancers (97%), whereas more than half of the non-addicted females had oral cancers (53%). Conclusions: Addicted patients commonly have oral cavity cancers. This might be due to the habit of chewing tobacco and/or betel nut that addicted patients have. Non-addicted patients are commonly young females. It is likely that no single known factor is responsible for HNSCC in non-addicted patients, and several occupational exposure studies in future may be important to the etiology of non-addicted patients. (author)

[en] Any measurement scheme involving interference of quantum states of the electromagnetic field necessarily mixes information about the spatiotemporal structure of these fields and quantum states in the recorded data. We show that in this case, a trade-off is possible between extracting information about the quantum states and the structure of the underlying fields, with the modal overlap being either a goal or a convenient tool of the reconstruction. We show that varying quantum states in a controlled way allows one to infer temporal profiles of modes. Vice versa, for the known quantum state of the probe and controlled variable overlap, one can infer the quantum state of the signal. We demonstrate this trade-off by performing an experiment using the simplest on–off detection in an unbalanced weak homodyning scheme. For the single-mode case, we demonstrate experimentally inference of the overlap and a few-photon signal state. Moreover, we show theoretically that the same single-detector scheme is sufficient even for arbitrary multi-mode fields. (paper)

[en] The physical nature of any quantum source guarantees the existence of an effective Hilbert space of finite dimension, the physical sector, in which its state is completely characterized with arbitrarily high accuracy. The extraction of this sector is essential for state tomography. We show that the physical sector of a state, defined in some pre-chosen basis, can be systematically retrieved with a procedure using only data collected from a set of commuting quantum measurement outcomes, with no other assumptions about the source. We demonstrate the versatility and efficiency of the physical-sector extraction by applying it to simulated and experimental data for quantum light sources, as well as quantum systems of finite dimensions. (paper)

[en] Using the ARGUS detector at the DORIS II storage ring we have searched for B⁰anti B⁰ oscillations in Y(4S) decays. One explicitly mixed event, a decay Y(4S) → B⁰B⁰, has been completely reconstructed. Furthermore, we observe a 4.0 standard deviation signal of 24.8 events with like-sign lepton pairs and a 3.0 standard deviation signal of 4.1 events containing one reconstructed B⁰(anti B⁰) and an additional fast l⁺(l^-). This leads to the conclusion that B⁰-anti B⁰ mixing is substantial. For the mixing parameter we obtain r = 0.21±0.08. (orig.)

[en] Using the ARGUS detector at DORIS we have observed the production of the charged Dsup(*) meson in e⁺e^- annihilation at a centre of mass energy of 10 GeV. The Dsup(*) fragmentation function has been measured using the decay channels Dsup(*+)->D⁰π⁺ with D⁰->K^-π⁺ and K^-π⁺π⁺π^-. We find sigmaxBr for the channels D⁰->K^-π⁺ and D⁰->K^-π⁺π⁺π^- to be (23.6+-2.2+-4.7) pb and (51.0+-4.6+-15.5) pb respectively, and the ratio of branching ratios Br(D⁰->K^-π⁺π⁺π^-)/Br(D⁰->K^-π⁺)=2.17+-0.28+-0.23. In addition we measure the mass difference M(Dsup(*+))-M(D⁰) to be (145.46+-0.07+-0.03) MeV, and set an upper limit for D⁰-anti D⁰ mixing of 0.11. (orig.)

[en] Using the ARGUS detector at DORIS, we have observed the production of Fsup(+-) mesons in e⁺e^- annihilation at a centre of mass energy of 10 GeV through their subsequent decays into PHIπsup(+-) and PHIπ⁺π^-πsup(+-). The values obtained for [R(e⁺e^- -> F x). Branching Ratio] are (1.47 +- 0.32 +- 0.20)% and (1.63 +- 0.42 +- 0.41)% respectively. The observed mass is (1973.6 +- 2.6 +- 3.0) MeV/c². The F momentum spectrum is as expected for the fragmentation of c quarks into charmed mesons, but is somewhat softer than for fragmentation into Dsup(*) mesons. The relevant angular distributions are consistent with a spin zero assignment of the F meson. (orig.)

[en] We have investigated the Y -> γtautau using tagged Y mesons from the decay Y' -> π⁺π^-Y. The photon spectrum exhibits no monochromatic line corresponding to a narrow object decaying into a tau pair and is fully compatible with the expected background contributions. The branching ratio Br(Y -> tau⁺tau^-) is determined to be (3.07 +- 0.46 +- 0.22)%. (orig.)

[en] Using the ARGUS detector at DORIS we have obtained evidence for a resonance which decays into an F meson and a photon. The observed mass is 2109 +- 9 +- 7 MeV, which is 144 +- 9 +- 7 MeV greater than the F meson mass. Its properties are consistent with those of the Fsup(*) meson with Jsup(P) = 1^-. (orig.)

[en] Using the ARGUS detector at DORIS we have obtained evidence for a resonance which decays into an F meson and a photon. The observed mass is 2109 +- 9 +- 7 MeV, which is 144 +- 9 +- 7 MeV greater than the F meson mass. Its properties are consistent with those of the Fsup(*) meson with Jsup(P)=1^-. (orig.)