start as1aem1.rs

crates/ekore/src/anomalous_dimensions/unpolarized/spacelike.rs

@@ -8,6 +8,7 @@ use num::complex::Complex;
 use num::Zero;
 pub mod aem1;
 pub mod as1;
+pub mod as1aem1;
 pub mod as2;
 pub mod as3;
 

crates/ekore/src/anomalous_dimensions/unpolarized/spacelike/as1aem1.rs

@@ -0,0 +1,37 @@
+//! The $O(a_s^1a_{em}^1)$ Altarelli-Parisi splitting kernels.
+use num::complex::Complex;
+
+use crate::constants::CF;
+use crate::harmonics::cache::{Cache, K};
+
+/// Compute the $O(a_s^1a_{em}^1)$ photon-quark anomalous dimension.
+///
+/// Implements Eq. (36) of
+pub fn gamma_phq(c: &mut Cache, _nf: u8) -> Complex<f64> {
+    let N = c.n();
+    let S1 = c.get(K::S1);
+    let S2 = c.get(K::S2);
+
+    #[rustfmt::skip]
+    let tmp_const =
+        2.0
+        * (
+            -4.0
+            - 12.0 * N
+            - N.powu(2)
+            + 28.0 * N.powu(3)
+            + 43.0 * N.powu(4)
+            + 30.0 * N.powu(5)
+            + 12.0 * N.powu(6)
+        ) / ((-1.0 + N) * N.powu(3) * (1.0 + N).powu(3));
+
+    #[rustfmt::skip]
+    let tmp_S1 = -4.0
+        * (10.0 + 27.0 * N + 25.0 * N.powu(2) + 13.0 * N.powu(3) + 5.0 * N.powu(4))
+        / ((-1.0 + N) * N * (1.0 + N).powu(3));
+
+    let tmp_S12 = 4.0 * (2.0 + N + N.powu(2)) / ((-1.0 + N) * N * (1.0 + N));
+    let tmp_S2 = 4.0 * (2.0 + N + N.powu(2)) / ((-1.0 + N) * N * (1.0 + N));
+
+    CF * (tmp_const + tmp_S1 * S1 + tmp_S12 * S1.powu(2) + tmp_S2 * S2)
+}