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Analytic Threads - Annual Newsletters 2014-2020, Messiah University Jan 2020

Analytic Threads - Annual Newsletters 2014-2020, Messiah University

Educator Scholarship & Departmental Newsletters

Faculty and student updates. Analytic Threads is the annual newsletter of the Department of Computing, Mathematics and Physics at Messiah University. It is sent annually to alumni and is also available electronically at the website messiah.edu/cmp


Features Of The Structure, Development, And Activity Of The Zebrafish Noradrenergic System Explored In New Crispr Transgenic Lines, Matthew J. Farrar, Kristine E. Kolkman, Joseph R. Fetcho Jan 2018

Features Of The Structure, Development, And Activity Of The Zebrafish Noradrenergic System Explored In New Crispr Transgenic Lines, Matthew J. Farrar, Kristine E. Kolkman, Joseph R. Fetcho

Educator Scholarship & Departmental Newsletters

The noradrenergic (NA) system of vertebrates is implicated in learning, memory, arousal, and neuroinflammatory responses, but is difficult to access experimentally. Small and optically transparent, larval zebrafish offer the prospect of exploration of NA structure and function in an intact animal. We made multiple transgenic zebrafish lines using the CRISPR/Cas9 system to insert fluorescent reporters upstream of slc6a2, the norepinephrine transporter gene. These lines faithfully express reporters in NA cell populations, including the locus coeruleus (LC), which contains only about 14 total neurons. We used the lines in combination with two‐photon microscopy to explore the structure and projections of the …


Search For T Violation In Charm Meson Decays, Abaz Kryemadhi Jan 2005

Search For T Violation In Charm Meson Decays, Abaz Kryemadhi

Educator Scholarship & Departmental Newsletters

Using data from the FOCUS (E831) experiment, we have searched for T violation in charm meson decays using the four-body decay channels D0→K−K+π−π+, D+→KS0K+π−π+, and Ds+→KS0K+π−π+. The T violation asymmetry is obtained using triple-product correlations and assuming the validity of the CPT theorem. We find the asymmetry values to be ATviol(D0)=0.010±0.057(stat.)±0.037(syst.), ATviol(D+)=0.023±0.062(stat.)±0.022(syst.), and ATviol(Ds+)=−0.036±0.067(stat.)±0.023(syst.). Each measurement is consistent with no T violation. New measurements of the CP asymmetries for some of these decay modes are also presented.


Study Of Λc+ Cabibbo Favored Decays Containing A Λ Baryon In The Final State, Abaz Kryemadhi Jan 2005

Study Of Λc+ Cabibbo Favored Decays Containing A Λ Baryon In The Final State, Abaz Kryemadhi

Educator Scholarship & Departmental Newsletters

Using data from the FOCUS experiment (FNAL–E831), we study the decay of Λc+ baryons into final states containing a Λ hyperon. The branching fractions of Λc+ into Λπ+, Λπ+π+π− and ΛK¯0K+ relative to that into pK−π+ are measured to be 0.217±0.013±0.020, 0.508±0.024±0.024 and 0.142±0.018±0.022, respectively. We also report new measurements of Γ(Λc+→Σ0π+)Γ(Λc+→Λπ+)=1.09±0.11±0.19, Γ(Λc+→Σ0π+π+π−)Γ(Λc+→Λπ+π+π−)=0.26±0.06±0.09 and Γ(Λc+→Ξ(1690)0(ΛK¯0)K+)Γ(Λc+→ΛK¯0K+)=0.32±0.10±0.04. Further, an analysis of the subresonant structure for the Λc+→Λπ+π+π− decay mode is presented.


Measurement Of The Branching Ratio Of The Decay D0→Π−Μ+Ν Relative To D0→K−Μ+Ν, Abaz Kryemadhi Jan 2005

Measurement Of The Branching Ratio Of The Decay D0→Π−Μ+Ν Relative To D0→K−Μ+Ν, Abaz Kryemadhi

Educator Scholarship & Departmental Newsletters

We present a new measurement of the branching ratio of the Cabibbo suppressed decay D0→π−μ+ν relative to the Cabibbo favored decay D0→K−μ+ν and an improved measurement of the ratio |f+π(0)/f+K(0)|. Our results are 0.074±0.008±0.007 for the branching ratio and 0.85±0.04±0.04±0.01 for the form factor ratio, respectively.


Study Of The Cabibbo-Suppressed Decay Modes D0→Π−Π+ And D0→K−K+, Abaz Kryemadhi Jan 2003

Study Of The Cabibbo-Suppressed Decay Modes D0→Π−Π+ And D0→K−K+, Abaz Kryemadhi

Educator Scholarship & Departmental Newsletters

Using data from the FOCUS (E831) experiment at Fermilab, we present a new measurement for the branching ratios of the Cabibbo-suppressed decay modes D0→π−π+ and D0→K−K+. We measured: Γ(D0→K−K+)/Γ(D0→π−π+)=2.81±0.10(stat)±0.06(syst), Γ(D0→K−K+)/Γ(D0→K−π+)=0.0993±0.0014(stat)±0.0014(syst), and Γ(D0→π−π+)/Γ(D0→K−π+)=0.0353±0.0012(stat)±0.0006(syst). These values have been combined with other experimental data to extract the ratios of isospin amplitudes and the phase shifts for the D→KK and D→ππ decay channels.


Effect Of Chemical Sputtering On The Growth And Structural Evolution Of Magnetron Sputtered Cnx Thin Films, Niklas Hellgren, Mats P.J Jõesaar, Esteban Broitman, Per Sandström, Lars Hultman, Jan-Eric Sundgren Feb 2001

Effect Of Chemical Sputtering On The Growth And Structural Evolution Of Magnetron Sputtered Cnx Thin Films, Niklas Hellgren, Mats P.J Jõesaar, Esteban Broitman, Per Sandström, Lars Hultman, Jan-Eric Sundgren

Educator Scholarship & Departmental Newsletters

The growth and microstructure evolution of carbon nitride CNx (0≤x≤0.35) films, deposited by reactive d.c. magnetron sputtering in Ar/N2 discharges has been studied. The substrate temperature TS varied between 100 and 550°C, and the N2 fraction in the discharge gas varied from 0 to 100%. It is found that the deposition rate and film morphology show strong dependence on TS and nitrogen fraction. For growth temperature of 100°C, the films are amorphous, and essentially unaffected by the nitrogen fraction. For TS>200°C, however, the nitrogen fraction has more significant effect on the growth and …


Nanoindentation And Strain Characteristics Of Nanostructured Boride/Nitride Films, Niklas Hellgren, R A. Andrievskii, G V. Kalinnikov, P Sandstrom, D V. Shtanskii Sep 2000

Nanoindentation And Strain Characteristics Of Nanostructured Boride/Nitride Films, Niklas Hellgren, R A. Andrievskii, G V. Kalinnikov, P Sandstrom, D V. Shtanskii

Educator Scholarship & Departmental Newsletters

The hardness, elastic modulus, and elastic recovery of nanostructured boride/nitride films 1–2 µm thick have been investigated by the nanoindentation technique under the maximum loads over a wide range (from 5 to 100 mN). It is demonstrated that only the hardness parameters remain constant at small loads (5–30 mN). The data obtained are discussed and compared with the parameters determined by other methods.


Nitrogen 1s Electron Binding Energy Assignment In Carbon Nitride Thin Films With Different Structures, Niklas Hellgren, Wei Tao Zheng, Ke Zhao Xing, Michael Lögdlund, Åsa A. Johansson, U Gelivs, William R. Salaneck, Jan Eric Sundgren Oct 1997

Nitrogen 1s Electron Binding Energy Assignment In Carbon Nitride Thin Films With Different Structures, Niklas Hellgren, Wei Tao Zheng, Ke Zhao Xing, Michael Lögdlund, Åsa A. Johansson, U Gelivs, William R. Salaneck, Jan Eric Sundgren

Educator Scholarship & Departmental Newsletters

Carbon nitride thin films deposited by dc unbalanced magnetron sputtering have been analyzed by high-resolution X-ray photoelectron spectroscopy (XPS) and Raman spectroscopy. The XPS data show that N 1s binding states depend on substrate temperature (Ts). By comparison with the Raman spectra, N 1s binding states are assigned in which nitrogen atoms are mainly bound to sp2 and sp3 carbon atoms at Ts = 100°C, whereas at Ts = 500°C nitrogen atoms are mainly bonded to sp2, sp3 and sp1 carbon atoms.