We have measured the radiation tolerance of poly-crystalline and single-crystalline diamonds grown by the chemical vapor deposition (CVD) process by measuring the charge collected before and after irradiation in a 50 m pitch strip detector fabricated on each diamond sample. We irradiated one group of sensors with 800 MeV protons, and a second group of sensors with 24 GeV protons, in steps, to protons cm⁻² and protons cm⁻² respectively. We observe the sum of mean drift paths for electrons and holes for both poly-crystalline CVD diamond and single-crystalline CVD diamond decreases with irradiation fluence from its initial value according to a simple damage curve characterized by a damage constant for each irradiation energy and the irradiation fluence. We find for each irradiation energy the damage constant, for poly-crystalline CVD diamond to be the same within statistical errors as the damage constant for single-crystalline CVD diamond. We find the damage constant for diamond irradiated with 24 GeV protons to be and the damage constant for diamond irradiated with 800 MeV protons to be . Moreover, we observe the pulse height decreases with fluence for poly-crystalline CVD material and within statistical errors does not change with fluence for single-crystalline CVD material for both 24 GeV proton irradiation and 800 MeV proton irradiation. Finally, we have measured the uniformity of each sample as a function of fluence and observed that for poly-crystalline CVD diamond the samples become more uniform with fluence while for single-crystalline CVD diamond the uniformity does not change with fluence.

We measured the radiation tolerance of commercially available diamonds grown by the Chemical Vapor Deposition process by measuring the charge created by a 120 GeV hadron beam in a 50 $\mathsf{\mu }\mathrm{m}$ pitch strip detector fabricated on each diamond sample before and after irradiation. We irradiated one group of samples with 70 MeV protons, a second group of samples with fast reactor neutrons (defined as energy greater than $0.1$ MeV), and a third group of samples with 200 MeV pions, in steps, to ($8.8\pm 0.9$) × 10¹⁵ protons/cm², ($1.43\pm 0.14$) × 10¹⁶ neutrons/cm², and ($6.5\pm 1.4$) × 10¹⁴ pions/cm², respectively. By observing the charge induced due to the separation of electron–hole pairs created by the passage of the hadron beam through each sample, on an event-by-event basis, as a function of irradiation fluence, we conclude all datasets can be described by a first-order damage equation and independently calculate the damage constant for 70 MeV protons, fast reactor neutrons, and 200 MeV pions. We find the damage constant for diamond irradiated with 70 MeV protons to be $1.62\pm 0.07\left(\mathrm{stat}\right)\pm 0.16\left(\mathrm{syst}\right)\times$ 10⁻¹⁸ cm²$/(p\mathsf{\mu }\mathrm{m})$, the damage constant for diamond irradiated with fast reactor neutrons to be $2.65\pm 0.13\left(\mathrm{stat}\right)\pm 0.18\left(\mathrm{syst}\right)\times$ 10⁻¹⁸ cm²$/(n\mathsf{\mu }\mathrm{m})$, and the damage constant for diamond irradiated with 200 MeV pions to be $2.0\pm 0.2\left(\mathrm{stat}\right)\pm 0.5\left(\mathrm{syst}\right)\times$ 10⁻¹⁸ cm²$/(\pi \mathsf{\mu }\mathrm{m})$. The damage constants from this measurement were analyzed together with our previously published 24 GeV proton irradiation and 800 MeV proton irradiation damage constant data to derive the first comprehensive set of relative damage constants for Chemical Vapor Deposition diamond. We find 70 MeV protons are 2.60 ± 0.29 times more damaging than 24 GeV protons, fast reactor neutrons are 4.3 ± 0.4 times more damaging than 24 GeV protons, and 200 MeV pions are 3.2 ± 0.8 more damaging than 24 GeV protons. We also observe the measured data can be described by a universal damage curve for all proton, neutron, and pion irradiations we performed of Chemical Vapor Deposition diamond. Finally, we confirm the spatial uniformity of the collected charge increases with fluence for polycrystalline Chemical Vapor Deposition diamond, and this effect can also be described by a universal curve.

Measurements are presented of the single-diffractive dijet cross section and the diffractive cross section as a function of the proton fractional momentum loss $$\xi $$ξ and the four-momentum transfer squared t. Both processes $${\text{ p }{}{}} {\text{ p }{}{}} \rightarrow {\text{ p }{}{}} {\text{ X }} $$p p → p X and $${\text{ p }{}{}} {\text{ p }{}{}} \rightarrow {\text{ X }} {\text{ p }{}{}} $$p p → X p , i.e. with the proton scattering to either side of the interaction point, are measured, where $${\text{ X }} $$X includes at least two jets; the results of the two processes are averaged. The analyses are based on data collected simultaneously with the CMS and TOTEM detectors at the LHC in proton–proton collisions at $$\sqrt{s} = 8\,\text {Te}\text {V} $$s = 8 Te during a dedicated run with $$\beta ^{*} = 90\,\text {m} $$β ∗ = 90 m at low instantaneous luminosity and correspond to an integrated luminosity of $$37.5{\,\text {nb}^{-1}} $$37.5 nb - 1 . The single-diffractive dijet cross section $$\sigma ^{{\text{ p }{}{}} {\text{ X }}}_{\mathrm {jj}}$$σ jj p X , in the kinematic region $$\xi < 0.1$$ξ < 0.1 , $$0.03< |t | < 1\,\text {Ge}\text {V} ^2$$0.03 < | t | < 1 Ge 2 , with at least two jets with transverse momentum $$p_{\mathrm {T}} > 40\,\text {Ge}\text {V} $$p T > 40 Ge , and pseudorapidity $$|\eta | < 4.4$$| η | < 4.4 , is $$21.7 \pm 0.9\,\text {(stat)} \,^{+3.0}_{-3.3}\,\text {(syst)} \pm 0.9\,\text {(lumi)} \,\text {nb} $$21.7 ± 0.9 (stat) - 3.3 + 3.0 (syst) ± 0.9 (lumi) nb . The ratio of the single-diffractive to inclusive dijet yields, normalised per unit of $$\xi $$ξ , is presented as a function of x, the longitudinal momentum fraction of the proton carried by the struck parton. The ratio in the kinematic region defined above, for x values in the range $$-2.9 \le \log _{10} x \le -1.6$$- 2.9 ≤ log 10 x ≤ - 1.6 , is $$R = (\sigma ^{{\text{ p }{}{}} {\text{ X }}}_{\mathrm {jj}}/\Delta \xi )/\sigma _{\mathrm {jj}} = 0.025 \pm 0.001\,\text {(stat)} \pm 0.003\,\text {(syst)} $$R = ( σ jj p X / Δ ξ ) / σ jj = 0.025 ± 0.001 (stat) ± 0.003 (syst) , where $$\sigma ^{{\text{ p }{}{}} {\text{ X }}}_{\mathrm {jj}}$$σ jj p X and $$\sigma _{\mathrm {jj}}$$σ jj are the single-diffractive and inclusive dijet cross sections, respectively. The results are compared with predictions from models of diffractive and nondiffractive interactions. Monte Carlo predictions based on the HERA diffractive parton distribution functions agree well with the data when corrected for the effect of soft rescattering between the spectator partons.

A Correction to this paper has been published: https://doi.org/10.1140/epjc/s10052-020-08562-y

Diamond is a material in use at many nuclear and high energy facilities due to its inherent radiation tolerance and ease of use. We have characterized detectors based on chemical vapor deposition (CVD) diamond before and after proton irradiation. We present preliminary results of the spatial resolution of unirradiated and irradiated CVD diamond strip sensors. In addition, we measured the pulse height versus particle rate of unirradiated and irradiated polycrystalline CVD (pCVD) diamond pad detectors up to a particle flux of $20\,\mathrm{MHz/cm^2}$ and a fluence up to $4 \times 10^{15}\,n/\mathrm{cm^2}$.

We have measured the radiation tolerance of chemical vapor deposition (CVD) diamond against protons and neutrons. The relative radiation damage constant of 24 GeV protons, 800 MeV protons, 70 MeV protons, and fast reactor neutrons is presented. The results are used to combine the measured data into a universal damage curve for diamond material.