
^{10}C (2004TI06)(See Energy Level Diagrams for ^{10}C) GENERAL: References to articles on general properties of ^{10}C published since the previous review (1988AJ01) are grouped into categories and listed, along with brief descriptions of each item, in the General Tables for ^{10}C located on our website at: (www.tunl.duke.edu/nucldata/General_Tables/10c.shtml). See also 2 in (1988AJ01) [Electromagnetic Transitions in A = 510] (in PDF or PS), 10.31 [Table of Energy Levels] (in PDF or PS) and 10.32 [Electromagnetic transitions in ^{10}C] (in PDF or PS). Mass of ^{10}C: The threshold energy for the ^{10}B(p, n)^{10}C reaction is 4877.03 ± 0.13 keV: then Q_{0} = 4430.30 ± 0.12 keV (1998BA83). Using the (2003AU03) masses for ^{10}B, p and n, the atomic mass excess is then 15698.8 ± 0.4 keV. However, we adopt the (2003AU03) value: 15698.6 ± 0.4 keV. See also unpublished work on ^{12}C(p, t)^{10}C that is quoted in (1984AJ01).
B(E2)(↓) for ^{10}C*(3.35) = 12.4 ± 2.0 e^{2} · fm^{4} (1968FI09).
The halflife of ^{10}C is 19.290 ± 0.012 sec (1990BA02), which is the average of 19280 ± 20 msec (1974AZ01), 19270 ± 80 msec (1963BA52), 19300 ± 41 msec (1990BA02) and 19294 ± 16 msec (1990BA02). The nucleus ^{10}C decays to ^{10}B*(0.7, 1.7): the branching ratios are (98.53 ± 0.02)% (1979AJ01) and (1.4645 ± 0.0019)% (1999FU04), respectively. See also the discussion of reaction 42 in ^{10}B. By measuring the relative polarization of positrons emitted from ^{10}C βdecay (pure GT) and ^{14}O (pure Fermi), ratio = 0.9996 ± 0.0036 (1988GI02, 1990CA41, 1991CA12), constraints on the scalar and tensor admixtures to the dominant vector and axial vector currents were determined as, C_{S}/C_{V}  C_{T}/C_{A} = 0.001 ± 0.009.
Elastic and inelastic scattering cross sections for ^{10}C*(0, 3.35) were measured at E(^{10}C) = 45.3 MeV/A (2003JO09). The data is best fit with M_{n}/M_{p} = 0.71 which gives M_{n} = 5.51 ± 1.07 fm^{2} when compared with the known value M_{p} = 7.87 ± 0.64 fm^{2}, which is derived from B(E2) = 62 ± 10 e^{2} · fm^{4}.
The π^{} production rates for various projectile and target combinations, including ^{6}Li + ^{4}He, were measured at 4.5 GeV/c per nucleon in (1993CH35). In general the observed π^{} production cross section falls off exponentially with increasing π^{} energy. In some cases the angular distributions show a slight dependence on target and projectile mass.
At E(^{3}He) = 235 MeV ^{10}C*(3.35) is populated (1984BI08). π^{} production in this reaction has also been studied by (1984BR22) at E(^{3}He) = 910 MeV.
Tetraneutron (n^{4}) production has been studied in this and in other reactions involving ^{10}C at E(^{7}Li) = 82 MeV (1987ALZG): it was not observed. However, evidence that is consistent with the existence of n^{4} is observed in the breakup of ^{14}Be (2002MA21).
Angular distributions of π^{} groups have been measured at E_{p} = 185 MeV (to ^{10}C*(0, 3.35, 5.28, 6.63)), at 200 MeV (g.s.), at 800 MeV (to ^{10}C*(0, 3.35, 5.3, 6.6)) [see (1984AJ01)] and at E_{pol. p} = 650 MeV (1986HO23; ^{10}C*(0, 3.35); also A_{y}). A_{y} measurements have also been reported at E_{pol. p} = 200 to 250 MeV: see (1984AJ01). At E_{p} = 800 MeV, the angular distributions of produced pions were measured for Be and C targets (1988BA58); they observed σ(0°)/σ(20°) ≈ 6.
In (1987SI18), calculations of polarization observables for ^{10}B(π^{+}, π^{0}) at 70 MeV and ^{10}B(π^{+}, η) at 460 MeV suggest that new measurements could provide insight into the singlechargeexchange reaction mechanism.
Level parameters for ^{10}C*(3.35) are E_{x} = 3352.7 ± 1.5 keV, τ_{m} = 155 ± 25 fsec, Γ_{γ} = 4.25 ± 0.69 meV. [See (1969PA09) and other references cited in (1974AJ01).] Angular distributions have been measured for the n_{0} and n_{1} groups and for the neutrons to ^{10}C*(5.2 ± 0.3) at E_{p} = 30 and 50 MeV [see (1974AJ01, 1979AJ01)] and for the n_{0} and n_{1} groups at E_{p} = 14.0, 14.3 and 14.6 MeV (1985SC08) and 15.8 and 18.6 MeV (1985GU1C). At E_{pol. p} = 186 MeV, angular distributions of neutrons were measured for θ = 0°  50° (1993WA06). Levels were observed at 0 [0^{+}], 3.35 [2^{+}], 5.3 [2^{+}], 6.6, ≈ 9, ≈ 10, and 16.5 MeV [(2^{+})] [J^{π} in brackets]. For E_{x} = 3.35 MeV, B(GT) = 0.03 and for 5.3 MeV, B(GT) = 0.68 ± 0.02. A multipole decomposition analysis suggests additional states at 17.2 and 20.2 with J^{π} = 2^{} or 1^{}, respectively. Higherlying resonances that were excited with E_{p} = 186 MeV protons, the GiantDipole Resonance (ΔL = 1, ΔS = 0) and the Giant Spin Dipole Resonance (ΔL = 1, ΔS = 1), are discussed in (1994RA23, 1994WA22, 1995YA12). In their analysis a broad peak from quasifree scattering, was estimated phenomenologically and subtracted from the excitation spectrum; a multipole decomposition analysis of the remaining structure indicated a prominent ΔL = 1 resonance around E_{x} = 17  20 MeV with a possible mixture of 2^{}, 1^{} and 2^{+} states (analogous to ^{10}B*(18.43, 18.8, 19.3, 20.1) and a small peak at E_{x} = 24 MeV (possible analog of the ^{10}B GDR). Data from E_{p} = 1 GeV were analyzed to develop a formalism for chargeexchange processes involving pion and Δisobar excitations (1994GA49). The threshold value for ^{10}B(p, n) was measured by (1989BA28); a subsequent analysis of that data, by (1998BA83), rigorously evaluated the proton beam energy spread (740 eV), nonuniform energy losses for all protons, and energy losses induced by ionizing target atoms prior to capture. The threshold value was determined to be E_{thresh.} = 4877.30 ± 0.13 keV, which yields Q_{0} = 4430.30 ± 0.12 keV for ^{10}B(p, n). At E_{p} = 7 and 9 MeV, thick target neutron and γray yields and relative ratios are measured for a compilation of protoninduced radiations that provide elemental analysis (1987RA23). Neutron production rates were measured for E_{cm} = 5.9 MeV (1988CHZN). The ^{10}B(p, n) cross section was measured at E_{p} = 4.8  30 MeV to evaluate the feasibility of producing isotopically enriched ^{10}CO_{2} for use in PET imaging (2000AL06).
Angular distributions have been measured at E(^{3}He) = 14 MeV and 217 MeV: see (1979AJ01). The latter [to ^{10}C*(0, 3.35, 5.6)] have been compared with microscopic calculations using a central + tensor interaction [J^{π} = 0^{+}, 2^{+}, 2^{+}, respectively]. Structures have been reported at E_{x} = 5.22 ± 0.04 [Γ = 225 ± 45 keV], 5.38 ± 0.07 [300 ± 60 keV] and 6.580 ± 0.020 MeV [190 ± 35 keV].
The production of radioactive isotopes from 100 and 190 GeV muons incident on a ^{12}C target was measured by (2000HA33) to estimate the μinduced backgrounds in large volume scintillator detector experiments.
Angular distributions have been reported at E_{p} = 30.0 to 54.1 MeV and at 80 MeV [see (1974AJ01, 1979AJ01, 1984AJ01)]. L = 0, 2 and 2 to ^{10}C*(0, 3.35, 5.28) thus leading to 0^{+}, 2^{+} and 2^{+}, respectively, for these states [but note that the "5.28 MeV" state is certainly unresolved]: see reaction 9 and 10.31 (in PDF or PS). ^{10}C*(6.6) is also populated. Two measurements of the excitation energy of ^{10}C*(3.4) are 3353.5 ± 1.0 keV and 3354.3 ± 1.1 keV: see (1984AJ01) [based on Q_{m}]. See also (1987KW01; theor.).
At E(^{3}He) = 70.3 MeV the angular distributions of the ^{6}He ions corresponding to the population of ^{10}C*(0, 3.35) have been measured. The group to ^{10}C*(3.35) is much more intense than the groundstate group: see (1979AJ01).
Spallation reaction rates for incident protons on ^{16}O and ^{12}C targets with E_{p} ≈ 50  250 MeV were calculated by (1999CH50) using the GNASH code. These reaction rates are important for estimating the secondary radiation induced in medical proton therapy treatment.
Total interaction cross sections of E(^{10}C) = 730 MeV/A projectiles were measured on ^{9}Be, ^{nat}C and ^{27}Al targets (1996OZ01). The deduced cross sections, σ = 752 ± 13, 795 ± 12 and 1171 ± 20 mb, respectively, indicate R_{rms}(^{10}C) = 2.27 ± 0.03 fm.
