Graphene was recently proposed as a material for heat removal owing to its extremely high thermal conductivity. We simulated heat propagation in silicon-on-insulator (SOI) circuits with and without ...graphene lateral heat spreaders. Numerical solutions of the heat-propagation equations were obtained using the finite-element method. The analysis was focused on the prototype SOI circuits with the metal-oxide-semiconductor field-effect transistors. It was found that the incorporation of graphene or few-layer graphene (FLG) layers with proper heat sinks can substantially lower the temperature of the localized hot spots. The maximum temperature in the transistor channels was studied as function of graphene's thermal conductivity and the thickness of FLG. The developed model and obtained results are important for the design of graphene heat spreaders and interconnects.
A
bstract
We present the first model-independent measurement of the CKM unitarity triangle angle
ϕ
3
using
B
±
→ D
(
K
S
0
π
+
π
−
π
0
)
K
±
decays, where
D
indicates either a
D
0
or
D
¯
0
meson. ...Measurements of the strong-phase difference of the
D →
K
S
0
π
+
π
−
π
0
amplitude obtained from CLEO-c data are used as input. This analysis is based on the full Belle data set of 772
×
10
6
B
B
¯
events collected at the Υ(4
S
) resonance. We obtain
ϕ
3
= (
5.7
−
8.8
+
10.2
±
3
.
5
±
5
.
7)
°
and the suppressed amplitude ratio
r
B
= 0
.
323
±
0
.
147
±
0
.
023
±
0
.
051. Here the first uncertainty is statistical, the second is the experimental systematic, and the third is due to the precision of the strong-phase parameters measured from CLEO-c data. The 95% confidence interval on
ϕ
3
is (
−
29
.
7
,
109
.
5)
°
, which is consistent with the current world average.
We report evidence for the charged charmed-strange baryon \(\Xi _{c}(2930)^+\) with a signal significance of 3.9 \(\sigma \) with systematic errors included. The charged \(\Xi _{c}(2930)^+\) is found ...in its decay to \(K_{S}^{0} \Lambda _{c}^+\) in the substructure of \(\bar{B}^{0} \rightarrow K^{0}_{S} \Lambda _{c}^{+} \bar{\Lambda }_{c}^{-}\) decays. The measured mass and width are \(2942.3 \pm 4.4 ({\mathrm{stat.}}) \pm {1.5}({\mathrm{syst.}})\) MeV/ \(c^{2}\) and \(14.8 \pm 8.8({\mathrm{stat.}}) \pm {2.5}({\mathrm{syst.}})\) MeV, respectively, and the product branching fraction is \(\mathcal{B}(\bar{B}^{0} \rightarrow \Xi _c(2930)^{+} \bar{\Lambda }_{c}^{-}) \mathcal{B}(\Xi _c(2930)^{+}\rightarrow \bar{K}^{0} \Lambda _{c}^{+})=2.37 \pm 0.51 ({\mathrm{stat.}})\pm 0.31({\mathrm{syst.}})\times 10^{-4}\) . We also measure \(\mathcal{B}(\bar{B}^{0} \rightarrow \bar{K}^{0} \Lambda _{c}^{+} \bar{\Lambda }_{c}^{-}) = 3.99 \pm 0.76({\mathrm{stat.}}) \pm 0.51({\mathrm{syst.}}) \times 10^{-4}\) with greater precision than previous experiments, and present the results of a search for the charmonium-like state Y(4660) and its spin partner, \(Y_{\eta }\) , in the \(\Lambda _{c}^{+}\bar{\Lambda }_{c}^{-}\) invariant mass spectrum. No clear signals of the Y(4660) or \(Y_{\eta }\) are observed and the 90% credibility level (C.L.) upper limits on their production rates are determined. These measurements are obtained from a sample of \((772\pm 11)\times 10^{6} B\bar{B}\) pairs collected at the \(\Upsilon (4S)\) resonance by the Belle detector at the KEKB asymmetric energy electron-positron collider.
Abstract We report evidence for the charged charmed-strange baryon $$\Xi _{c}(2930)^+$$ Ξc(2930)+ with a signal significance of 3.9$$\sigma $$ σ with systematic errors included. The charged $$\Xi ..._{c}(2930)^+$$ Ξc(2930)+ is found in its decay to $$K_{S}^{0} \Lambda _{c}^+$$ KS0Λc+ in the substructure of $$\bar{B}^{0} \rightarrow K^{0}_{S} \Lambda _{c}^{+} \bar{\Lambda }_{c}^{-}$$ B¯0→KS0Λc+Λ¯c- decays. The measured mass and width are $$2942.3 \pm 4.4 ({\mathrm{stat.}}) \pm {1.5}({\mathrm{syst.}})$$ 2942.3±4.4(stat.)±1.5(syst.) MeV/$$c^{2}$$ c2 and $$14.8 \pm 8.8({\mathrm{stat.}}) \pm {2.5}({\mathrm{syst.}})$$ 14.8±8.8(stat.)±2.5(syst.) MeV, respectively, and the product branching fraction is $$\mathcal{B}(\bar{B}^{0} \rightarrow \Xi _c(2930)^{+} \bar{\Lambda }_{c}^{-}) \mathcal{B}(\Xi _c(2930)^{+}\rightarrow \bar{K}^{0} \Lambda _{c}^{+})=2.37 \pm 0.51 ({\mathrm{stat.}})\pm 0.31({\mathrm{syst.}})\times 10^{-4}$$ B(B¯0→Ξc(2930)+Λ¯c-)B(Ξc(2930)+→K¯0Λc+)=2.37±0.51(stat.)±0.31(syst.)×10-4 . We also measure $$\mathcal{B}(\bar{B}^{0} \rightarrow \bar{K}^{0} \Lambda _{c}^{+} \bar{\Lambda }_{c}^{-}) = 3.99 \pm 0.76({\mathrm{stat.}}) \pm 0.51({\mathrm{syst.}}) \times 10^{-4}$$ B(B¯0→K¯0Λc+Λ¯c-)=3.99±0.76(stat.)±0.51(syst.)×10-4 with greater precision than previous experiments, and present the results of a search for the charmonium-like state Y(4660) and its spin partner, $$Y_{\eta }$$ Yη , in the $$\Lambda _{c}^{+}\bar{\Lambda }_{c}^{-}$$ Λc+Λ¯c- invariant mass spectrum. No clear signals of the Y(4660) or $$Y_{\eta }$$ Yη are observed and the 90% credibility level (C.L.) upper limits on their production rates are determined. These measurements are obtained from a sample of $$(772\pm 11)\times 10^{6} B\bar{B}$$ (772±11)×106BB¯ pairs collected at the $$\Upsilon (4S)$$ Υ(4S) resonance by the Belle detector at the KEKB asymmetric energy electron-positron collider.
We report evidence for the charged charmed-strange baryon Formula omitted with a signal significance of 3.9 Formula omitted with systematic errors included. The charged Formula omitted is found in ...its decay to Formula omitted in the substructure of Formula omitted decays. The measured mass and width are Formula omitted MeV/ Formula omitted and Formula omitted MeV, respectively, and the product branching fraction is Formula omitted. We also measure Formula omitted with greater precision than previous experiments, and present the results of a search for the charmonium-like state Y(4660) and its spin partner, Formula omitted, in the Formula omitted invariant mass spectrum. No clear signals of the Y(4660) or Formula omitted are observed and the 90% credibility level (C.L.) upper limits on their production rates are determined. These measurements are obtained from a sample of Formula omitted pairs collected at the Formula omitted resonance by the Belle detector at the KEKB asymmetric energy electron-positron collider.
We study bottomonium production in association with an Formula omitted meson in Formula omitted annihilations near the Formula omitted, at a centre-of-mass energy of Formula omitted GeV. The results ...are based on the 121.4 fb Formula omitted data sample collected by the Belle experiment at the asymmetric-energy KEKB collider. Only the Formula omitted meson is reconstructed and the missing-mass spectrum of Formula omitted candidates is investigated. We observe the Formula omitted process and find evidence for the Formula omitted process, while no significant signals of Formula omitted, Formula omitted, nor Formula omitted are found. Cross sections for the studied processes are reported.
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