If the incident proton collides with a proton bound in a nucleus, the threshold energy is lower because the target proton is bound . 如果入射質(zhì)子是與束縛在原子核內(nèi)的質(zhì)子相碰撞,那么閾能會低一些,因為作為靶的質(zhì)子是束縛著的。
It was found that the simple triangular shape distribution would cause " two - peaked " energy distribution near the threshold energy , which must affect the group transfer matrix 閾能處三角形能譜分布的近似描述,導(dǎo)致產(chǎn)生了群散射矩陣的“雙峰”現(xiàn)象,而閾能處矩形能譜分布使平均次級中子能量(
The relative momentum of two final particles and the cross section are zero at the threshold energy for an endothermic reaction , while the relative momentum of two initial particles is zero and the cross section at the threshold energy for an exothermic reaction is infinite 在吸熱反應(yīng)的閾能處,出射粒子的相對動量以及截面均為零。在放熱反應(yīng)的閾能處,入射粒子的相對動量為零,截面趨于無窮大。由于強子的動量僅提供如此低的質(zhì)心系能量,強子物質(zhì)中x 。
We also experimentally observed the effect of sodium atom - molecular collisions and sodium atom - atom collisions on the line - shape and intensity of fluorescence spectra . in addition , the optically pumped infrared stimulated emission and energy transfer up - conversion process are observed in pr3 + : y2sio5 , and with the threshold energy , temperature dependence and divergence angle for the stimulated radiation are measured 此外還研究了摻雜在固體y _ 2sio _ 5中的pr ~ ( 3 + )的光泵紅外受激輻射和能量轉(zhuǎn)移上轉(zhuǎn)換,分別測得了紅外受激輻射的閾值能量和發(fā)散角,并擬合得出了能量轉(zhuǎn)移速率。
In particle physics, the threshold energy for production of a particle is the minimum kinetic energy a pair of traveling particles must have when they collide. The threshold energy is always greater than or equal to the rest energy of the desired particle.